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• Web Services and code lists

  - by 0x0me

  Our team heavily discuss the issues how to handle code list in a web service definition. The design goal is to describe a provider API to query a system using various values. Some of them are catalogs resp. code lists. A catalog or code list is a set of key value pairs. There are different systems (at least 3) maintaining possibly different code lists. Each system should implement the provider API, whereas each system might have different code list for the same business entity eg. think of colors. One system know [(1,'red'),(2,'green')] and another one knows [(1,'lightgreen'),(2,'darkgreen'),(3,'red')] etc. The access to the different provider API implementations will be encapsulated by a query service, but there is already one candidate which might use at least one provider API directly. The current options to design the API discussed are: use an abstract code list in the interface definition: the web service interface defines a well known set of code list which are expected to be used for querying and returning data. Each API provider implementation has to mapped the request and response values from those abstract codelist to the system specific one. let the query component handle the code list: the encapsulating query service knows the code list set of each provider API implementation and takes care of mapping the input and output to the system specific code lists of the queried system. do not use code lists in the query definition at all: Just query code lists by a plain string and let the provider API implementation figure out the right value. This might lead to a loose of information and possibly many false positives, due to the fact that the input string could not be canonical mapped to a code list value (eg. green - lightgreen or green - darkgreen or both) What are your experiences resp. solutions to such a problem? Could you give any recommendation?

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• Opinion on "loop invariants", and are these frequently used in the industry?

  - by Michael Aaron Safyan

  I was thinking back to my freshman year at college (five years ago) when I took an exam to place-out of intro-level computer science. There was a question about loop invariants, and I was wondering if loop invariants are really necessary in this case or if the question was simply a bad example... the question was to write an iterative definition for a factorial function, and then to prove that the function was correct. The code that I provided for the factorial function was as follows: public static int factorial(int x) { if ( x < 0 ){ throw new IllegalArgumentException("Parameter must be = 0"); }else if ( x == 0 ){ return 1; }else{ int result = 1; for ( int i = 1; i <= x; i++ ){ result*=i; } return result; } } My own proof of correctness was a proof by cases, and in each I asserted that it was correct by definition (x! is undefined for negative values, 0! is 1, and x! is 1*2*3...*x for a positive value of x). The professor wanted me to prove the loop using a loop invariant; however, my argument was that it was correct "by definition", because the definition of "x!" for a positive integer x is "the product of the integers from 1... x", and the for-loop in the else clause is simply a literal translation of this definition. Is a loop invariant really needed as a proof of correctness in this case? How complicated must a loop be before a loop invariant (and proper initialization and termination conditions) become necessary for a proof of correctness? Additionally, I was wondering... how often are such formal proofs used in the industry? I have found that about half of my courses are very theoretical and proof-heavy and about half are very implementation and coding-heavy, without any formal or theoretical material. How much do these overlap in practice? If you do use proofs in the industry, when do you apply them (always, only if it's complicated, rarely, never)?

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• Schema to support dynamic properties

  - by Johan Fredrik Varen

  Hi people. I'm working on an editor that enables its users to create "object" definitions in real-time. A definition can contain zero or more properties. A property has a name a type. Once a definition is created, a user can create an object of that definition and set the property values of that object. So by the click of a mouse-button, the user should ie. be able to create a new definition called "Bicycle", and add the property "Size" of type "Numeric". Then another property called "Name" of type "Text", and then another property called "Price" of type "Numeric". Once that is done, the user should be able to create a couple of "Bicycle" objects and fill in the "Name" and "Price" property values of each bike. Now, I've seen this feature in several software products, so it must be a well-known concept. My problem started when I sat down and tried to come up with a DB schema to support this data structure, because I want the property values to be stored using the appropriate column types. Ie. a numeric property value is stored as, say, an INT in the database, and a textual property value is stored as VARCHAR. First, I need a table that will hold all my object definitions: Table obj_defs id | name | ---------------- 1 | "Bicycle" | 2 | "Book" | Then I need a table for holding what sort of properties each object definition should have: Table prop_defs id | obj_def_id | name | type | ------------------------------------ 1 | 1 | "Size" | ? | 2 | 1 | "Name" | ? | 3 | 1 | "Price" | ? | 4 | 2 | "Title" | ? | 5 | 2 | "Author" | ? | 6 | 2 | "ISBN" | ? | I would also need a table that holds each object: Table objects id | created | updated | ------------------------------ 1 | 2011-05-14 | 2011-06-15 | 2 | 2011-05-14 | 2011-06-15 | 3 | 2011-05-14 | 2011-06-15 | Finally, I need a table that will hold the actual property values of each object, and one solution is for this table to have one column for each possible value type, such as this: Table prop_vals id | prop_def_id | object_id | numeric | textual | boolean | ------------------------------------------------------------ 1 | 1 | 1 | 27 | | | 2 | 2 | 1 | | "Trek" | | 3 | 3 | 1 | 1249 | | | 4 | 1 | 2 | 26 | | | 5 | 2 | 2 | | "GT" | | 6 | 3 | 2 | 159 | | | 7 | 4 | 3 | | "It" | | 8 | 5 | 3 | | "King" | | 9 | 6 | 4 | 9 | | | If I implemented this schema, what would the "type" column of the prop_defs table hold? Integers that each map to a column name, varchars that simply hold the column name? Any other possibilities? Would a stored procedure help me out here in some way? And what would the SQL for fetching the "name" property of object 2 look like?

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• DirectX works for 64-bit but not 32-bit

  - by dtbarne

  I'm trying to play a game (Civilization 5) which was previously working but no longer. I believe I've narrowed it down to a DirectX issue because I get an error running dxdiag.exe in 32 bit mode. My goal (at least I believe) is to get Direct3D Acceleration "Enabled" in dxdiag (as it is in 64 bit dxdiag). A very similar issue is here: http://answers.microsoft.com/en-us/windows/forum/windows_7-gaming/direct3d-acceleration-is-not-available-in-windows/4c345e6e-dc68-e011-8dfc-68b599b31bf5?page=1 The proposed answer, which looks very promising, doesn't seem to work for me. Like other users in that thread, HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Direct3D\Drivers does not have a SoftwareOnly key to change. I even tried manually adding it as a string and dword, to no avail. I have a NVIDIA GeForce GT 525M, and before you ask, yes I've tried updating (also uninstalling, reinstalling) my drivers. I've also tried doing the same with DirectX (and Civilization 5 for that matter). Been debugging for some 4+ hours now after a full day of work and I've run out of ideas. I'm hoping somebody knows the solution here! :) Here's what I see when I open dxdiag: DxDiag has detected that there mgiht have been a problem accessing Direct3D the last time this program was used. Would you like to bypass Direct3D this time? No - Crash Yes - Works, but in Display tab: DirectDraw Acceleration: Disabled Direct3D Acceleration: Not Available AGP Texture Acceleration: Not Available If I click "Run 64-bit DxDiag", all three are "Enabled". I should also note that I've tried the following steps as Microsoft suggests, but I'm not able to do so as the "Change Settings" button is disabled. Some programs run very slowly—or not at all—unless Microsoft DirectDraw or Direct3D hardware acceleration is turned on. To determine this, click the Display tab, and then under DirectX Features, check to see whether DirectDraw, Direct3D, and AGP Texture Acceleration appear as Enabled. If not, try turning on hardware acceleration. Click to open Screen Resolution. Click Advanced settings. Click the Troubleshoot tab, and then click Change settings. If you're prompted for an administrator password or confirmation, type the password or provide confirmation. Move the Hardware Acceleration slider to Full. Full dxdiag dump: ------------------ System Information ------------------ Time of this report: 11/8/2012, 23:13:24 Machine name: DTBARNE Operating System: Windows 7 Professional 64-bit (6.1, Build 7601) Service Pack 1 (7601.win7sp1_gdr.120830-0333) Language: English (Regional Setting: English) System Manufacturer: Dell Inc. System Model: Dell System XPS L502X BIOS: Default System BIOS Processor: Intel(R) Core(TM) i5-2450M CPU @ 2.50GHz (4 CPUs), ~2.5GHz Memory: 8192MB RAM Available OS Memory: 8086MB RAM Page File: 2466MB used, 13704MB available Windows Dir: C:\Windows DirectX Version: DirectX 11 DX Setup Parameters: Not found User DPI Setting: Using System DPI System DPI Setting: 96 DPI (100 percent) DWM DPI Scaling: Disabled DxDiag Version: 6.01.7601.17514 32bit Unicode DxDiag Previously: Crashed in Direct3D (stage 2). Re-running DxDiag with "dontskip" command line parameter or choosing not to bypass information gathering when prompted might result in DxDiag successfully obtaining this information ------------ DxDiag Notes ------------ Display Tab 1: No problems found. Sound Tab 1: No problems found. Sound Tab 2: No problems found. Input Tab: No problems found. -------------------- DirectX Debug Levels -------------------- Direct3D: 0/4 (retail) DirectDraw: 0/4 (retail) DirectInput: 0/5 (retail) DirectMusic: 0/5 (retail) DirectPlay: 0/9 (retail) DirectSound: 0/5 (retail) DirectShow: 0/6 (retail) --------------- Display Devices --------------- Card name: Intel(R) HD Graphics 3000 Manufacturer: Chip type: DAC type: Device Key: Enum\PCI\VEN_8086&DEV_0126&SUBSYS_04B61028&REV_09 Display Memory: Dedicated Memory: n/a Shared Memory: n/a Current Mode: 1920 x 1080 (32 bit) (60Hz) Monitor Name: Generic PnP Monitor Monitor Model: Monitor Id: Native Mode: Output Type: Driver Name: Driver File Version: () Driver Version: DDI Version: Driver Model: WDDM 1.1 Driver Attributes: Final Retail Driver Date/Size: , 0 bytes WHQL Logo'd: n/a WHQL Date Stamp: n/a Device Identifier: Vendor ID: Device ID: SubSys ID: Revision ID: Driver Strong Name: oem11.inf:IntelGfx.NTamd64.6.0:iSNBM0:8.15.10.2696:pci\ven_8086&dev_0126&subsys_04b61028 Rank Of Driver: 00E60001 Video Accel: Deinterlace Caps: n/a D3D9 Overlay: DXVA-HD: DDraw Status: Disabled D3D Status: Not Available AGP Status: Not Available ------------- Sound Devices ------------- Description: Speakers (High Definition Audio Device) Default Sound Playback: Yes Default Voice Playback: Yes Hardware ID: HDAUDIO\FUNC_01&VEN_10EC&DEV_0665&SUBSYS_102804B6&REV_1000 Manufacturer ID: 1 Product ID: 65535 Type: WDM Driver Name: HdAudio.sys Driver Version: 6.01.7601.17514 (English) Driver Attributes: Final Retail WHQL Logo'd: Yes Date and Size: 11/20/2010 22:23:47, 350208 bytes Other Files: Driver Provider: Microsoft HW Accel Level: Basic Cap Flags: 0xF1F Min/Max Sample Rate: 100, 200000 Static/Strm HW Mix Bufs: 1, 0 Static/Strm HW 3D Bufs: 0, 0 HW Memory: 0 Voice Management: No EAX(tm) 2.0 Listen/Src: No, No I3DL2(tm) Listen/Src: No, No Sensaura(tm) ZoomFX(tm): No Description: Digital Audio (S/PDIF) (High Definition Audio Device) Default Sound Playback: No Default Voice Playback: No Hardware ID: HDAUDIO\FUNC_01&VEN_10EC&DEV_0665&SUBSYS_102804B6&REV_1000 Manufacturer ID: 1 Product ID: 65535 Type: WDM Driver Name: HdAudio.sys Driver Version: 6.01.7601.17514 (English) Driver Attributes: Final Retail WHQL Logo'd: Yes Date and Size: 11/20/2010 22:23:47, 350208 bytes Other Files: Driver Provider: Microsoft HW Accel Level: Basic Cap Flags: 0xF1F Min/Max Sample Rate: 100, 200000 Static/Strm HW Mix Bufs: 1, 0 Static/Strm HW 3D Bufs: 0, 0 HW Memory: 0 Voice Management: No EAX(tm) 2.0 Listen/Src: No, No I3DL2(tm) Listen/Src: No, No Sensaura(tm) ZoomFX(tm): No --------------------- Sound Capture Devices --------------------- Description: Microphone (High Definition Audio Device) Default Sound Capture: Yes Default Voice Capture: Yes Driver Name: HdAudio.sys Driver Version: 6.01.7601.17514 (English) Driver Attributes: Final Retail Date and Size: 11/20/2010 22:23:47, 350208 bytes Cap Flags: 0x1 Format Flags: 0xFFFFF ------------------- DirectInput Devices ------------------- Device Name: Mouse Attached: 1 Controller ID: n/a Vendor/Product ID: n/a FF Driver: n/a Device Name: Keyboard Attached: 1 Controller ID: n/a Vendor/Product ID: n/a FF Driver: n/a Poll w/ Interrupt: No ----------- USB Devices ----------- + USB Root Hub | Vendor/Product ID: 0x8086, 0x1C26 | Matching Device ID: usb\root_hub20 | Service: usbhub | +-+ Generic USB Hub | | Vendor/Product ID: 0x8087, 0x0024 | | Location: Port_#0001.Hub_#0002 | | Matching Device ID: usb\class_09 | | Service: usbhub ---------------- Gameport Devices ---------------- ------------ PS/2 Devices ------------ + Standard PS/2 Keyboard | Matching Device ID: *pnp0303 | Service: i8042prt | + Terminal Server Keyboard Driver | Matching Device ID: root\rdp_kbd | Upper Filters: kbdclass | Service: TermDD | + Synaptics PS/2 Port TouchPad | Matching Device ID: *dll04b6 | Upper Filters: SynTP | Service: i8042prt | + Terminal Server Mouse Driver | Matching Device ID: root\rdp_mou | Upper Filters: mouclass | Service: TermDD ------------------------ Disk & DVD/CD-ROM Drives ------------------------ Drive: C: Free Space: 26.2 GB Total Space: 122.0 GB File System: NTFS Model: M4-CT128M4SSD2 ATA Device Drive: D: Model: Optiarc DVDRWBD BC-5540H ATA Device Driver: c:\windows\system32\drivers\cdrom.sys, 6.01.7601.17514 (English), , 0 bytes -------------- System Devices -------------- Name: High Definition Audio Controller Device ID: PCI\VEN_8086&DEV_1C20&SUBSYS_04B61028&REV_05\3&11583659&0&D8 Driver: n/a Name: PCI standard host CPU bridge Device ID: PCI\VEN_8086&DEV_0104&SUBSYS_04B61028&REV_09\3&11583659&0&00 Driver: n/a Name: PCI standard PCI-to-PCI bridge Device ID: PCI\VEN_8086&DEV_1C1A&SUBSYS_04B61028&REV_B5\3&11583659&0&E5 Driver: n/a Name: PCI standard PCI-to-PCI bridge Device ID: PCI\VEN_8086&DEV_0101&SUBSYS_20108086&REV_09\3&11583659&0&08 Driver: n/a Name: PCI standard PCI-to-PCI bridge Device ID: PCI\VEN_8086&DEV_1C18&SUBSYS_04B61028&REV_B5\3&11583659&0&E4 Driver: n/a Name: Intel(R) Centrino(R) Advanced-N 6230 Device ID: PCI\VEN_8086&DEV_0091&SUBSYS_52218086&REV_34\4&2634DE8D&0&00E1 Driver: n/a Name: PCI standard ISA bridge Device ID: PCI\VEN_8086&DEV_1C4B&SUBSYS_04B61028&REV_05\3&11583659&0&F8 Driver: n/a Name: PCI standard PCI-to-PCI bridge Device ID: PCI\VEN_8086&DEV_1C16&SUBSYS_04B61028&REV_B5\3&11583659&0&E3 Driver: n/a Name: Realtek PCIe GBE Family Controller Device ID: PCI\VEN_10EC&DEV_8168&SUBSYS_04B61028&REV_06\4&109EAB2F&0&00E5 Driver: n/a Name: Intel(R) Management Engine Interface Device ID: PCI\VEN_8086&DEV_1C3A&SUBSYS_04B61028&REV_04\3&11583659&0&B0 Driver: n/a Name: PCI standard PCI-to-PCI bridge Device ID: PCI\VEN_8086&DEV_1C12&SUBSYS_04B61028&REV_B5\3&11583659&0&E1 Driver: n/a Name: NVIDIA GeForce GT 525M Device ID: PCI\VEN_10DE&DEV_0DF5&SUBSYS_04B61028&REV_A1\4&4DCA75F&0&0008 Driver: n/a Name: Standard Enhanced PCI to USB Host Controller Device ID: PCI\VEN_8086&DEV_1C2D&SUBSYS_04B61028&REV_05\3&11583659&0&D0 Driver: n/a Name: PCI standard PCI-to-PCI bridge Device ID: PCI\VEN_8086&DEV_1C10&SUBSYS_04B61028&REV_B5\3&11583659&0&E0 Driver: n/a Name: Standard Enhanced PCI to USB Host Controller Device ID: PCI\VEN_8086&DEV_1C26&SUBSYS_04B61028&REV_05\3&11583659&0&E8 Driver: n/a Name: Standard AHCI 1.0 Serial ATA Controller Device ID: PCI\VEN_8086&DEV_1C03&SUBSYS_04B61028&REV_05\3&11583659&0&FA Driver: n/a Name: SM Bus Controller Device ID: PCI\VEN_8086&DEV_1C22&SUBSYS_04B61028&REV_05\3&11583659&0&FB Driver: n/a Name: Intel(R) HD Graphics 3000 Device ID: PCI\VEN_8086&DEV_0126&SUBSYS_04B61028&REV_09\3&11583659&0&10 Driver: n/a Name: Renesas Electronics USB 3.0 Host Controller Device ID: PCI\VEN_1033&DEV_0194&SUBSYS_04B61028&REV_04\4&3494AC3A&0&00E3 Driver: n/a ------------------ DirectShow Filters ------------------ DirectShow Filters: WMAudio Decoder DMO,0x00800800,1,1,WMADMOD.DLL,6.01.7601.17514 WMAPro over S/PDIF DMO,0x00600800,1,1,WMADMOD.DLL,6.01.7601.17514 WMSpeech Decoder DMO,0x00600800,1,1,WMSPDMOD.DLL,6.01.7601.17514 MP3 Decoder DMO,0x00600800,1,1,mp3dmod.dll,6.01.7600.16385 Mpeg4s Decoder DMO,0x00800001,1,1,mp4sdecd.dll,6.01.7600.16385 WMV Screen decoder DMO,0x00600800,1,1,wmvsdecd.dll,6.01.7601.17514 WMVideo Decoder DMO,0x00800001,1,1,wmvdecod.dll,6.01.7601.17514 Mpeg43 Decoder DMO,0x00800001,1,1,mp43decd.dll,6.01.7600.16385 Mpeg4 Decoder DMO,0x00800001,1,1,mpg4decd.dll,6.01.7600.16385 DV Muxer,0x00400000,0,0,qdv.dll,6.06.7601.17514 Color Space Converter,0x00400001,1,1,quartz.dll,6.06.7601.17713 WM ASF Reader,0x00400000,0,0,qasf.dll,12.00.7601.17514 Screen Capture filter,0x00200000,0,1,wmpsrcwp.dll,12.00.7601.17514 AVI Splitter,0x00600000,1,1,quartz.dll,6.06.7601.17713 VGA 16 Color Ditherer,0x00400000,1,1,quartz.dll,6.06.7601.17713 SBE2MediaTypeProfile,0x00200000,0,0,sbe.dll,6.06.7601.17528 Microsoft DTV-DVD Video Decoder,0x005fffff,2,4,msmpeg2vdec.dll,6.01.7140.0000 AC3 Parser Filter,0x00600000,1,1,mpg2splt.ax,6.06.7601.17528 StreamBufferSink,0x00200000,0,0,sbe.dll,6.06.7601.17528 MJPEG Decompressor,0x00600000,1,1,quartz.dll,6.06.7601.17713 MPEG-I Stream Splitter,0x00600000,1,2,quartz.dll,6.06.7601.17713 SAMI (CC) Parser,0x00400000,1,1,quartz.dll,6.06.7601.17713 VBI Codec,0x00600000,1,4,VBICodec.ax,6.06.7601.17514 MPEG-2 Splitter,0x005fffff,1,0,mpg2splt.ax,6.06.7601.17528 Closed Captions Analysis Filter,0x00200000,2,5,cca.dll,6.06.7601.17514 SBE2FileScan,0x00200000,0,0,sbe.dll,6.06.7601.17528 Microsoft MPEG-2 Video Encoder,0x00200000,1,1,msmpeg2enc.dll,6.01.7601.17514 Internal Script Command Renderer,0x00800001,1,0,quartz.dll,6.06.7601.17713 MPEG Audio Decoder,0x03680001,1,1,quartz.dll,6.06.7601.17713 DV Splitter,0x00600000,1,2,qdv.dll,6.06.7601.17514 Video Mixing Renderer 9,0x00200000,1,0,quartz.dll,6.06.7601.17713 Microsoft MPEG-2 Encoder,0x00200000,2,1,msmpeg2enc.dll,6.01.7601.17514 ACM Wrapper,0x00600000,1,1,quartz.dll,6.06.7601.17713 Video Renderer,0x00800001,1,0,quartz.dll,6.06.7601.17713 MPEG-2 Video Stream Analyzer,0x00200000,0,0,sbe.dll,6.06.7601.17528 Line 21 Decoder,0x00600000,1,1,qdvd.dll,6.06.7601.17835 Video Port Manager,0x00600000,2,1,quartz.dll,6.06.7601.17713 Video Renderer,0x00400000,1,0,quartz.dll,6.06.7601.17713 VPS Decoder,0x00200000,0,0,WSTPager.ax,6.06.7601.17514 WM ASF Writer,0x00400000,0,0,qasf.dll,12.00.7601.17514 VBI Surface Allocator,0x00600000,1,1,vbisurf.ax,6.01.7601.17514 File writer,0x00200000,1,0,qcap.dll,6.06.7601.17514 iTV Data Sink,0x00600000,1,0,itvdata.dll,6.06.7601.17514 iTV Data Capture filter,0x00600000,1,1,itvdata.dll,6.06.7601.17514 DVD Navigator,0x00200000,0,3,qdvd.dll,6.06.7601.17835 Overlay Mixer2,0x00200000,1,1,qdvd.dll,6.06.7601.17835 AVI Draw,0x00600064,9,1,quartz.dll,6.06.7601.17713 RDP DShow Redirection Filter,0xffffffff,1,0,DShowRdpFilter.dll, Microsoft MPEG-2 Audio Encoder,0x00200000,1,1,msmpeg2enc.dll,6.01.7601.17514 WST Pager,0x00200000,1,1,WSTPager.ax,6.06.7601.17514 MPEG-2 Demultiplexer,0x00600000,1,1,mpg2splt.ax,6.06.7601.17528 DV Video Decoder,0x00800000,1,1,qdv.dll,6.06.7601.17514 SampleGrabber,0x00200000,1,1,qedit.dll,6.06.7601.17514 Null Renderer,0x00200000,1,0,qedit.dll,6.06.7601.17514 MPEG-2 Sections and Tables,0x005fffff,1,0,Mpeg2Data.ax,6.06.7601.17514 Microsoft AC3 Encoder,0x00200000,1,1,msac3enc.dll,6.01.7601.17514 StreamBufferSource,0x00200000,0,0,sbe.dll,6.06.7601.17528 Smart Tee,0x00200000,1,2,qcap.dll,6.06.7601.17514 Overlay Mixer,0x00200000,0,0,qdvd.dll,6.06.7601.17835 AVI Decompressor,0x00600000,1,1,quartz.dll,6.06.7601.17713 AVI/WAV File Source,0x00400000,0,2,quartz.dll,6.06.7601.17713 Wave Parser,0x00400000,1,1,quartz.dll,6.06.7601.17713 MIDI Parser,0x00400000,1,1,quartz.dll,6.06.7601.17713 Multi-file Parser,0x00400000,1,1,quartz.dll,6.06.7601.17713 File stream renderer,0x00400000,1,1,quartz.dll,6.06.7601.17713 Microsoft DTV-DVD Audio Decoder,0x005fffff,1,1,msmpeg2adec.dll,6.01.7140.0000 StreamBufferSink2,0x00200000,0,0,sbe.dll,6.06.7601.17528 AVI Mux,0x00200000,1,0,qcap.dll,6.06.7601.17514 Line 21 Decoder 2,0x00600002,1,1,quartz.dll,6.06.7601.17713 File Source (Async.),0x00400000,0,1,quartz.dll,6.06.7601.17713 File Source (URL),0x00400000,0,1,quartz.dll,6.06.7601.17713 Infinite Pin Tee Filter,0x00200000,1,1,qcap.dll,6.06.7601.17514 Enhanced Video Renderer,0x00200000,1,0,evr.dll,6.01.7601.17514 BDA MPEG2 Transport Information Filter,0x00200000,2,0,psisrndr.ax,6.06.7601.17669 MPEG Video Decoder,0x40000001,1,1,quartz.dll,6.06.7601.17713 WDM Streaming Tee/Splitter Devices: Tee/Sink-to-Sink Converter,0x00200000,1,1,ksproxy.ax,6.01.7601.17514 Video Compressors: WMVideo8 Encoder DMO,0x00600800,1,1,wmvxencd.dll,6.01.7600.16385 WMVideo9 Encoder DMO,0x00600800,1,1,wmvencod.dll,6.01.7600.16385 MSScreen 9 encoder DMO,0x00600800,1,1,wmvsencd.dll,6.01.7600.16385 DV Video Encoder,0x00200000,0,0,qdv.dll,6.06.7601.17514 MJPEG Compressor,0x00200000,0,0,quartz.dll,6.06.7601.17713 Cinepak Codec by Radius,0x00200000,1,1,qcap.dll,6.06.7601.17514 Intel IYUV codec,0x00200000,1,1,qcap.dll,6.06.7601.17514 Intel IYUV codec,0x00200000,1,1,qcap.dll,6.06.7601.17514 Microsoft RLE,0x00200000,1,1,qcap.dll,6.06.7601.17514 Microsoft Video 1,0x00200000,1,1,qcap.dll,6.06.7601.17514 Audio Compressors: WM Speech Encoder DMO,0x00600800,1,1,WMSPDMOE.DLL,6.01.7600.16385 WMAudio Encoder DMO,0x00600800,1,1,WMADMOE.DLL,6.01.7600.16385 IMA ADPCM,0x00200000,1,1,quartz.dll,6.06.7601.17713 PCM,0x00200000,1,1,quartz.dll,6.06.7601.17713 Microsoft ADPCM,0x00200000,1,1,quartz.dll,6.06.7601.17713 GSM 6.10,0x00200000,1,1,quartz.dll,6.06.7601.17713 CCITT A-Law,0x00200000,1,1,quartz.dll,6.06.7601.17713 CCITT u-Law,0x00200000,1,1,quartz.dll,6.06.7601.17713 MPEG Layer-3,0x00200000,1,1,quartz.dll,6.06.7601.17713 Audio Capture Sources: Microphone (High Definition Aud,0x00200000,0,0,qcap.dll,6.06.7601.17514 PBDA CP Filters: PBDA DTFilter,0x00600000,1,1,CPFilters.dll,6.06.7601.17528 PBDA ETFilter,0x00200000,0,0,CPFilters.dll,6.06.7601.17528 PBDA PTFilter,0x00200000,0,0,CPFilters.dll,6.06.7601.17528 Midi Renderers: Default MidiOut Device,0x00800000,1,0,quartz.dll,6.06.7601.17713 Microsoft GS Wavetable Synth,0x00200000,1,0,quartz.dll,6.06.7601.17713 WDM Streaming Capture Devices: HD Audio Microphone 2,0x00200000,1,1,ksproxy.ax,6.01.7601.17514 Integrated Webcam,0x00200000,1,2,ksproxy.ax,6.01.7601.17514 WDM Streaming Rendering Devices: HD Audio Headphone/Speakers,0x00200000,1,1,ksproxy.ax,6.01.7601.17514 HD Audio SPDIF out,0x00200000,1,1,ksproxy.ax,6.01.7601.17514 BDA Network Providers: Microsoft ATSC Network Provider,0x00200000,0,1,MSDvbNP.ax,6.06.7601.17514 Microsoft DVBC Network Provider,0x00200000,0,1,MSDvbNP.ax,6.06.7601.17514 Microsoft DVBS Network Provider,0x00200000,0,1,MSDvbNP.ax,6.06.7601.17514 Microsoft DVBT Network Provider,0x00200000,0,1,MSDvbNP.ax,6.06.7601.17514 Microsoft Network Provider,0x00200000,0,1,MSNP.ax,6.06.7601.17514 Video Capture Sources: Integrated Webcam,0x00200000,1,2,ksproxy.ax,6.01.7601.17514 Multi-Instance Capable VBI Codecs: VBI Codec,0x00600000,1,4,VBICodec.ax,6.06.7601.17514 BDA Transport Information Renderers: BDA MPEG2 Transport Information Filter,0x00600000,2,0,psisrndr.ax,6.06.7601.17669 MPEG-2 Sections and Tables,0x00600000,1,0,Mpeg2Data.ax,6.06.7601.17514 BDA CP/CA Filters: Decrypt/Tag,0x00600000,1,1,EncDec.dll,6.06.7601.17708 Encrypt/Tag,0x00200000,0,0,EncDec.dll,6.06.7601.17708 PTFilter,0x00200000,0,0,EncDec.dll,6.06.7601.17708 XDS Codec,0x00200000,0,0,EncDec.dll,6.06.7601.17708 WDM Streaming Communication Transforms: Tee/Sink-to-Sink Converter,0x00200000,1,1,ksproxy.ax,6.01.7601.17514 Audio Renderers: Speakers (High Definition Audio,0x00200000,1,0,quartz.dll,6.06.7601.17713 Default DirectSound Device,0x00800000,1,0,quartz.dll,6.06.7601.17713 Default WaveOut Device,0x00200000,1,0,quartz.dll,6.06.7601.17713 Digital Audio (S/PDIF) (High De,0x00200000,1,0,quartz.dll,6.06.7601.17713 DirectSound: Digital Audio (S/PDIF) (High Definition Audio Device),0x00200000,1,0,quartz.dll,6.06.7601.17713 DirectSound: Speakers (High Definition Audio Device),0x00200000,1,0,quartz.dll,6.06.7601.17713 --------------- EVR Power Information --------------- Current Setting: {651288E5-A7ED-4076-A96B-6CC62D848FE1} (Balanced) Quality Flags: 2576 Enabled: Force throttling Allow half deinterlace Allow scaling Decode Power Usage: 100 Balanced Flags: 1424 Enabled: Force throttling Allow batching Force half deinterlace Force scaling Decode Power Usage: 50 PowerFlags: 1424 Enabled: Force throttling Allow batching Force half deinterlace Force scaling Decode Power Usage: 0

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• Using the Onboard VGA output with a PCIe video card. Both nVidia

  - by sebikul

  I have 2 video cards, one On board, a nVidia 6150SE nForce 430 and a PCIe nVidia GeForce GT 220 1GB DDR2 RAM I have already configured the PCIe card to use the dual monitor feature, using the VGA and HDMI ports, but now I want to add a third monitor, using the On board VGA port I have managed to enable the On board graphics processor, which is taking 400MB of ram, but I cant manage to use it, nvidia-settings does not detect it, like it's not usable (but is there) My questions are the following: How can I manage to get the On board VGA display to work together with the PCIe graphics card? If possible, how can I recover those 400 MB the on board card is taking (even without being used) or how can I get it to use the PCIe card available memory? System Details: Linux 2.6.35-28-generic i686 Ubuntu 10.10 (All updates installed) NVIDIA Driver Version: 260.19.06 (Official) If more info is needed please let me know. Here is the lspci output when the On board card is disabled: 00:00.0 RAM memory: nVidia Corporation MCP61 Memory Controller (rev a1) 00:01.0 ISA bridge: nVidia Corporation MCP61 LPC Bridge (rev a2) 00:01.1 SMBus: nVidia Corporation MCP61 SMBus (rev a2) 00:01.2 RAM memory: nVidia Corporation MCP61 Memory Controller (rev a2) 00:01.3 Co-processor: nVidia Corporation MCP61 SMU (rev a2) 00:02.0 USB Controller: nVidia Corporation MCP61 USB Controller (rev a3) 00:02.1 USB Controller: nVidia Corporation MCP61 USB Controller (rev a3) 00:04.0 PCI bridge: nVidia Corporation MCP61 PCI bridge (rev a1) 00:05.0 Audio device: nVidia Corporation MCP61 High Definition Audio (rev a2) 00:06.0 IDE interface: nVidia Corporation MCP61 IDE (rev a2) 00:07.0 Bridge: nVidia Corporation MCP61 Ethernet (rev a2) 00:08.0 IDE interface: nVidia Corporation MCP61 SATA Controller (rev a2) 00:09.0 PCI bridge: nVidia Corporation MCP61 PCI Express bridge (rev a2) 00:0b.0 PCI bridge: nVidia Corporation MCP61 PCI Express bridge (rev a2) 00:0c.0 PCI bridge: nVidia Corporation MCP61 PCI Express bridge (rev a2) 00:0d.0 VGA compatible controller: nVidia Corporation C61 [GeForce 6150SE nForce 430] (rev a2) 00:18.0 Host bridge: Advanced Micro Devices [AMD] K8 [Athlon64/Opteron] HyperTransport Technology Configuration 00:18.1 Host bridge: Advanced Micro Devices [AMD] K8 [Athlon64/Opteron] Address Map 00:18.2 Host bridge: Advanced Micro Devices [AMD] K8 [Athlon64/Opteron] DRAM Controller 00:18.3 Host bridge: Advanced Micro Devices [AMD] K8 [Athlon64/Opteron] Miscellaneous Control 01:09.0 Ethernet controller: Intel Corporation 82557/8/9/0/1 Ethernet Pro 100 (rev 08) 02:00.0 VGA compatible controller: nVidia Corporation GT216 [GeForce GT 220] (rev a2) 02:00.1 Audio device: nVidia Corporation High Definition Audio Controller (rev a1) And this is when both are enabled: 00:00.0 RAM memory: nVidia Corporation MCP61 Memory Controller (rev a1) 00:01.0 ISA bridge: nVidia Corporation MCP61 LPC Bridge (rev a2) 00:01.1 SMBus: nVidia Corporation MCP61 SMBus (rev a2) 00:01.2 RAM memory: nVidia Corporation MCP61 Memory Controller (rev a2) 00:01.3 Co-processor: nVidia Corporation MCP61 SMU (rev a2) 00:02.0 USB Controller: nVidia Corporation MCP61 USB Controller (rev a3) 00:02.1 USB Controller: nVidia Corporation MCP61 USB Controller (rev a3) 00:04.0 PCI bridge: nVidia Corporation MCP61 PCI bridge (rev a1) 00:05.0 Audio device: nVidia Corporation MCP61 High Definition Audio (rev a2) 00:06.0 IDE interface: nVidia Corporation MCP61 IDE (rev a2) 00:07.0 Bridge: nVidia Corporation MCP61 Ethernet (rev a2) 00:08.0 IDE interface: nVidia Corporation MCP61 SATA Controller (rev a2) 00:09.0 PCI bridge: nVidia Corporation MCP61 PCI Express bridge (rev a2) 00:0b.0 PCI bridge: nVidia Corporation MCP61 PCI Express bridge (rev a2) 00:0c.0 PCI bridge: nVidia Corporation MCP61 PCI Express bridge (rev a2) 00:0d.0 VGA compatible controller: nVidia Corporation C61 [GeForce 6150SE nForce 430] (rev a2) 00:18.0 Host bridge: Advanced Micro Devices [AMD] K8 [Athlon64/Opteron] HyperTransport Technology Configuration 00:18.1 Host bridge: Advanced Micro Devices [AMD] K8 [Athlon64/Opteron] Address Map 00:18.2 Host bridge: Advanced Micro Devices [AMD] K8 [Athlon64/Opteron] DRAM Controller 00:18.3 Host bridge: Advanced Micro Devices [AMD] K8 [Athlon64/Opteron] Miscellaneous Control 01:09.0 Ethernet controller: Intel Corporation 82557/8/9/0/1 Ethernet Pro 100 (rev 08) 02:00.0 VGA compatible controller: nVidia Corporation GT216 [GeForce GT 220] (rev a2) 02:00.1 Audio device: nVidia Corporation High Definition Audio Controller (rev a1) Output of lshw -class display: *-display description: VGA compatible controller product: GT216 [GeForce GT 220] vendor: nVidia Corporation physical id: 0 bus info: pci@0000:02:00.0 version: a2 width: 64 bits clock: 33MHz capabilities: pm msi pciexpress vga_controller bus_master cap_list rom configuration: driver=nvidia latency=0 resources: irq:18 memory:df000000-dfffffff memory:c0000000-cfffffff memory:da000000-dbffffff ioport:ef80(size=128) memory:def80000-deffffff *-display description: VGA compatible controller product: C61 [GeForce 6150SE nForce 430] vendor: nVidia Corporation physical id: d bus info: pci@0000:00:0d.0 version: a2 width: 64 bits clock: 66MHz capabilities: pm msi vga_controller bus_master cap_list rom configuration: driver=nvidia latency=0 resources: irq:22 memory:dd000000-ddffffff memory:b0000000-bfffffff memory:dc000000-dcffffff memory:deb40000-deb5ffff If what I'm looking for is not possible, please tell me, so I can disable the On board card and recover those 400MB of wasted RAM Thanks for your help!

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• PowerShell Script To Find Where SharePoint 2007 Features Are Activated

  - by Brian T. Jackett

  Recently I posted a script to find where SharePoint 2010 Features Are Activated.  I built the original version to use SharePoint 2010 PowerShell commandlets as that saved me a number of steps for filtering and gathering features at each level.  If there was ever demand for a 2007 version I could modify the script to handle that by using the object model instead of commandlets.  Just the other week a fellow SharePoint PFE Jason Gallicchio had a customer asking about a version for SharePoint 2007.  With a little bit of work I was able to convert the script to work against SharePoint 2007.   Solution    Below is the converted script that works against a SharePoint 2007 farm.  Note: There appears to be a bug with the 2007 version that does not give accurate results against a SharePoint 2010 farm.  I ran the 2007 version against a 2010 farm and got fewer results than my 2010 version of the script.  Discussing with some fellow PFEs I think the discrepancy may be due to sandboxed features, a new concept in SharePoint 2010.  I have not had enough time to test or confirm.  For the time being only use the 2007 version script against SharePoint 2007 farms and the 2010 version against SharePoint 2010 farms.    Note: This script is not optimized for medium to large farms.  In my testing it took 1-3 minutes to recurse through my demo environment.  This script is provided as-is with no warranty.  Run this in a smaller dev / test environment first. 001 002 003 004 005 006 007 008 009 010 011 012 013 014 015 016 017 018 019 020 021 022 023 024 025 026 027 028 029 030 031 032 033 034 035 036 037 038 039 040 041 042 043 044 045 046 047 048 049 050 051 052 053 054 055 056 057 058 059 060 061 062 063 064 065 066 067 068 069 070 function Get-SPFeatureActivated { # see full script for help info, removed for formatting [CmdletBinding()] param(     [Parameter(position = 1, valueFromPipeline=$true)]     [string]     $Identity )#end param     Begin     {         # load SharePoint assembly to access object model         [void][System.Reflection.Assembly]::LoadWithPartialName("Microsoft.SharePoint")             # declare empty array to hold results. Will add custom member for Url to show where activated at on objects returned from Get-SPFeature.         $results = @()                 $params = @{}     }     Process     {         if([string]::IsNullOrEmpty($Identity) -eq $false)         {             $params = @{Identity = $Identity}         }                 # create hashtable of farm features to lookup definition ids later         $farm = [Microsoft.SharePoint.Administration.SPFarm]::Local                         # check farm features         $results += ($farm.FeatureDefinitions | Where-Object {$_.Scope -eq "Farm"} | Where-Object {[string]::IsNullOrEmpty($Identity) -or ($_.DisplayName -eq $Identity)} |                          % {Add-Member -InputObject $_ -MemberType noteproperty -Name Url -Value ([string]::Empty) -PassThru} |                          Select-Object -Property Scope, DisplayName, Id, Url)                 # check web application features         $contentWebAppServices = $farm.services | ? {$_.typename -like "Windows SharePoint Services Web Application"}                 foreach($webApp in $contentWebAppServices.WebApplications)         {             $results += ($webApp.Features | Select-Object -ExpandProperty Definition | Where-Object {[string]::IsNullOrEmpty($Identity) -or ($_.DisplayName -eq $Identity)} |                          % {Add-Member -InputObject $_ -MemberType noteproperty -Name Url -Value $webApp.GetResponseUri(0).AbsoluteUri -PassThru} |                          Select-Object -Property Scope, DisplayName, Id, Url)                         # check site collection features in current web app             foreach($site in ($webApp.Sites))             {                 $results += ($site.Features | Select-Object -ExpandProperty Definition | Where-Object {[string]::IsNullOrEmpty($Identity) -or ($_.DisplayName -eq $Identity)} |                                  % {Add-Member -InputObject $_ -MemberType noteproperty -Name Url -Value $site.Url -PassThru} |                                  Select-Object -Property Scope, DisplayName, Id, Url)                                 # check site features in current site collection                 foreach($web in ($site.AllWebs))                 {                     $results += ($web.Features | Select-Object -ExpandProperty Definition | Where-Object {[string]::IsNullOrEmpty($Identity) -or ($_.DisplayName -eq $Identity)} |                                      % {Add-Member -InputObject $_ -MemberType noteproperty -Name Url -Value $web.Url -PassThru} |                                      Select-Object -Property Scope, DisplayName, Id, Url)                                                        $web.Dispose()                 }                 $site.Dispose()             }         }     }     End     {         $results     } } #end Get-SPFeatureActivated Get-SPFeatureActivated   Conclusion    I have posted this script to the TechNet Script Repository (click here).  As always I appreciate any feedback on scripts.  If anyone is motivated to run this 2007 version script against a SharePoint 2010 to see if they find any differences in number of features reported versus what they get with the 2010 version script I’d love to hear from you.         -Frog Out

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• Broken Views

  - by Ajarn Mark Caldwell

  “SELECT *” isn’t just hazardous to performance, it can actually return blatantly wrong information. There are a number of blog posts and articles out there that actively discourage the use of the SELECT * FROM …syntax.  The two most common explanations that I have seen are: Performance:  The SELECT * syntax will return every column in the table, but frequently you really only need a few of the columns, and so by using SELECT * your are retrieving large volumes of data that you don’t need, but the system has to process, marshal across tiers, and so on.  It would be much more efficient to only select the specific columns that you need. Future-proof:  If you are taking other shortcuts in your code, along with using SELECT *, you are setting yourself up for trouble down the road when enhancements are made to the system.  For example, if you use SELECT * to return results from a table into a DataTable in .NET, and then reference columns positionally (e.g. myDataRow[5]) you could end up with bad data if someone happens to add a column into position 3 and skewing all the remaining columns’ ordinal position.  Or if you use INSERT…SELECT * then you will likely run into errors when a new column is added to the source table in any position. And if you use SELECT * in the definition of a view, you will run into a variation of the future-proof problem mentioned above.  One of the guys on my team, Mike Byther, ran across this in a project we were doing, but fortunately he caught it while we were still in development.  I asked him to put together a test to prove that this was related to the use of SELECT * and not some other anomaly.  I’ll walk you through the test script so you can see for yourself what happens. We are going to create a table and two views that are based on that table, one of them uses SELECT * and the other explicitly lists the column names.  The script to create these objects is listed below. IF OBJECT_ID('testtab') IS NOT NULL DROP TABLE testtabgoIF OBJECT_ID('testtab_vw') IS NOT NULL DROP VIEW testtab_vwgo IF OBJECT_ID('testtab_vw_named') IS NOT NULL DROP VIEW testtab_vw_namedgo CREATE TABLE testtab (col1 NVARCHAR(5) null, col2 NVARCHAR(5) null)INSERT INTO testtab(col1, col2)VALUES ('A','B'), ('A','B')GOCREATE VIEW testtab_vw AS SELECT * FROM testtabGOCREATE VIEW testtab_vw_named AS SELECT col1, col2 FROM testtabgo Now, to prove that the two views currently return equivalent results, select from them. SELECT 'star', col1, col2 FROM testtab_vwSELECT 'named', col1, col2 FROM testtab_vw_named OK, so far, so good.  Now, what happens if someone makes a change to the definition of the underlying table, and that change results in a new column being inserted between the two existing columns?  (Side note, I normally prefer to append new columns to the end of the table definition, but some people like to keep their columns alphabetized, and for clarity for later people reviewing the schema, it may make sense to group certain columns together.  Whatever the reason, it sometimes happens, and you need to protect yourself and your code from the repercussions.) DROP TABLE testtabgoCREATE TABLE testtab (col1 NVARCHAR(5) null, col3 NVARCHAR(5) NULL, col2 NVARCHAR(5) null)INSERT INTO testtab(col1, col3, col2)VALUES ('A','C','B'), ('A','C','B')goSELECT 'star', col1, col2 FROM testtab_vwSELECT 'named', col1, col2 FROM testtab_vw_named I would have expected that the view using SELECT * in its definition would essentially pass-through the column name and still retrieve the correct data, but that is not what happens.  When you run our two select statements again, you see that the View that is based on SELECT * actually retrieves the data based on the ordinal position of the columns at the time that the view was created.  Sure, one work-around is to recreate the View, but you can’t really count on other developers to know the dependencies you have built-in, and they won’t necessarily recreate the view when they refactor the table. I am sure that there are reasons and justifications for why Views behave this way, but I find it particularly disturbing that you can have code asking for col2, but actually be receiving data from col3.  By the way, for the record, this entire scenario and accompanying test script apply to SQL Server 2008 R2 with Service Pack 1. So, let the developer beware…know what assumptions are in effect around your code, and keep on discouraging people from using SELECT * syntax in anything but the simplest of ad-hoc queries. And of course, let’s clean up after ourselves.  To eliminate the database objects created during this test, run the following commands. DROP TABLE testtabDROP VIEW testtab_vwDROP VIEW testtab_vw_named

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• file doesn't open, running outside of debugger results in seg fault (c++)

  - by misterich

  Hello (and thanks in advance) I'm in a bit of a quandry, I cant seem to figure out why I'm seg faulting. A couple of notes: It's for a course -- and sadly I am required to use use C-strings instead of std::string. Please dont fix my code (I wont learn that way and I will keep bugging you). please just point out the flaws in my logic and suggest a different function/way. platform: gcc version 4.4.1 on Suse Linux 11.2 (2.6.31 kernel) Here's the code main.cpp: // /////////////////////////////////////////////////////////////////////////////////// // INCLUDES (C/C++ Std Library) #include <cstdlib> /// EXIT_SUCCESS, EXIT_FAILURE #include <iostream> /// cin, cout, ifstream #include <cassert> /// assert // /////////////////////////////////////////////////////////////////////////////////// // DEPENDENCIES (custom header files) #include "dict.h" /// Header for the dictionary class // /////////////////////////////////////////////////////////////////////////////////// // PRE-PROCESSOR CONSTANTS #define ENTER '\n' /// Used to accept new lines, quit program. #define SPACE ' ' /// One way to end the program // /////////////////////////////////////////////////////////////////////////////////// // CUSTOM DATA TYPES /// File Namespace -- keep it local namespace { /// Possible program prompts to display for the user. enum FNS_Prompts { fileName_, /// prints out the name of the file noFile_, /// no file was passed to the program tooMany_, /// more than one file was passed to the program noMemory_, /// Not enough memory to use the program usage_, /// how to use the program word_, /// ask the user to define a word. notFound_, /// the word is not in the dictionary done_, /// the program is closing normally }; } // /////////////////////////////////////////////////////////////////////////////////// // Namespace using namespace std; /// Nothing special in the way of namespaces // /////////////////////////////////////////////////////////////////////////////////// // FUNCTIONS /** prompt() prompts the user to do something, uses enum Prompts for parameter. */ void prompt(FNS_Prompts msg /** determines the prompt to use*/) { switch(msg) { case fileName_ : { cout << ENTER << ENTER << "The file name is: "; break; } case noFile_ : { cout << ENTER << ENTER << "...Sorry, a dictionary file is needed. Try again." << endl; break; } case tooMany_ : { cout << ENTER << ENTER << "...Sorry, you can only specify one dictionary file. Try again." << endl; break; } case noMemory_ : { cout << ENTER << ENTER << "...Sorry, there isn't enough memory available to run this program." << endl; break; } case usage_ : { cout << "USAGE:" << endl << " lookup.exe [dictionary file name]" << endl << endl; break; } case done_ : { cout << ENTER << ENTER << "like Master P says, \"Word.\"" << ENTER << endl; break; } case word_ : { cout << ENTER << ENTER << "Enter a word in the dictionary to get it's definition." << ENTER << "Enter \"?\" to get a sorted list of all words in the dictionary." << ENTER << "... Press the Enter key to quit the program: "; break; } case notFound_ : { cout << ENTER << ENTER << "...Sorry, that word is not in the dictionary." << endl; break; } default : { cout << ENTER << ENTER << "something passed an invalid enum to prompt(). " << endl; assert(false); /// something passed in an invalid enum } } } /** useDictionary() uses the dictionary created by createDictionary * - prompts user to lookup a word * - ends when the user enters an empty word */ void useDictionary(Dictionary &d) { char *userEntry = new char; /// user's input on the command line if( !userEntry ) // check the pointer to the heap { cout << ENTER << MEM_ERR_MSG << endl; exit(EXIT_FAILURE); } do { prompt(word_); // test code cout << endl << "----------------------------------------" << endl << "Enter something: "; cin.getline(userEntry, INPUT_LINE_MAX_LEN, ENTER); cout << ENTER << userEntry << endl; }while ( userEntry[0] != NIL && userEntry[0] != SPACE ); // GARBAGE COLLECTION delete[] userEntry; } /** Program Entry * Reads in the required, single file from the command prompt. * - If there is no file, state such and error out. * - If there is more than one file, state such and error out. * - If there is a single file: * - Create the database object * - Populate the database object * - Prompt the user for entry * main() will return EXIT_SUCCESS upon termination. */ int main(int argc, /// the number of files being passed into the program char *argv[] /// pointer to the filename being passed into tthe program ) { // EXECUTE /* Testing code * / char tempFile[INPUT_LINE_MAX_LEN] = {NIL}; cout << "enter filename: "; cin.getline(tempFile, INPUT_LINE_MAX_LEN, '\n'); */ // uncomment after successful debugging if(argc <= 1) { prompt(noFile_); prompt(usage_); return EXIT_FAILURE; /// no file was passed to the program } else if(argc > 2) { prompt(tooMany_); prompt(usage_); return EXIT_FAILURE; /// more than one file was passed to the program } else { prompt(fileName_); cout << argv[1]; // print out name of dictionary file if( !argv[1] ) { prompt(noFile_); prompt(usage_); return EXIT_FAILURE; /// file does not exist } /* file.open( argv[1] ); // open file numEntries >> in.getline(file); // determine number of dictionary objects to create file.close(); // close file Dictionary[ numEntries ](argv[1]); // create the dictionary object */ // TEMPORARY FILE FOR TESTING!!!! //Dictionary scrabble(tempFile); Dictionary scrabble(argv[1]); // creaate the dicitonary object //*/ useDictionary(scrabble); // prompt the user, use the dictionary } // exit return EXIT_SUCCESS; /// terminate program. } Dict.h/.cpp #ifndef DICT_H #define DICT_H // /////////////////////////////////////////////////////////////////////////////////// // DEPENDENCIES (Custom header files) #include "entry.h" /// class for dictionary entries // /////////////////////////////////////////////////////////////////////////////////// // PRE-PROCESSOR MACROS #define INPUT_LINE_MAX_LEN 256 /// Maximum length of each line in the dictionary file class Dictionary { public : // // Do NOT modify the public section of this class // typedef void (*WordDefFunc)(const char *word, const char *definition); Dictionary( const char *filename ); ~Dictionary(); const char *lookupDefinition( const char *word ); void forEach( WordDefFunc func ); private : // // You get to provide the private members // // VARIABLES int m_numEntries; /// stores the number of entries in the dictionary Entry *m_DictEntry_ptr; /// points to an array of class Entry // Private Functions }; #endif ----------------------------------- // /////////////////////////////////////////////////////////////////////////////////// // INCLUDES (C/C++ Std Library) #include <iostream> /// cout, getline #include <fstream> // ifstream #include <cstring> /// strchr // /////////////////////////////////////////////////////////////////////////////////// // DEPENDENCIES (custom header files) #include "dict.h" /// Header file required by assignment //#include "entry.h" /// Dicitonary Entry Class // /////////////////////////////////////////////////////////////////////////////////// // PRE-PROCESSOR MACROS #define COMMA ',' /// Delimiter for file #define ENTER '\n' /// Carriage return character #define FILE_ERR_MSG "The data file could not be opened. Program will now terminate." #pragma warning(disable : 4996) /// turn off MS compiler warning about strcpy() // /////////////////////////////////////////////////////////////////////////////////// // Namespace reference using namespace std; // /////////////////////////////////////////////////////////////////////////////////// // PRIVATE MEMBER FUNCTIONS /** * Sorts the dictionary entries. */ /* static void sortDictionary(?) { // sort through the words using qsort } */ /** NO LONGER NEEDED?? * parses out the length of the first cell in a delimited cell * / int getWordLength(char *str /// string of data to parse ) { return strcspn(str, COMMA); } */ // /////////////////////////////////////////////////////////////////////////////////// // PUBLIC MEMBER FUNCTIONS /** constructor for the class * - opens/reads in file * - creates initializes the array of member vars * - creates pointers to entry objects * - stores pointers to entry objects in member var * - ? sort now or later? */ Dictionary::Dictionary( const char *filename ) { // Create a filestream, open the file to be read in ifstream dataFile(filename, ios::in ); /* if( dataFile.fail() ) { cout << FILE_ERR_MSG << endl; exit(EXIT_FAILURE); } */ if( dataFile.is_open() ) { // read first line of data // TEST CODE in.getline(dataFile, INPUT_LINE_MAX_LEN) >> m_numEntries; // TEST CODE char temp[INPUT_LINE_MAX_LEN] = {NIL}; // TEST CODE dataFile.getline(temp,INPUT_LINE_MAX_LEN,'\n'); dataFile >> m_numEntries; /** Number of terms in the dictionary file * \todo find out how many lines in the file, subtract one, ingore first line */ //create the array of entries m_DictEntry_ptr = new Entry[m_numEntries]; // check for valid memory allocation if( !m_DictEntry_ptr ) { cout << MEM_ERR_MSG << endl; exit(EXIT_FAILURE); } // loop thru each line of the file, parsing words/def's and populating entry objects for(int EntryIdx = 0; EntryIdx < m_numEntries; ++EntryIdx) { // VARIABLES char *tempW_ptr; /// points to a temporary word char *tempD_ptr; /// points to a temporary def char *w_ptr; /// points to the word in the Entry object char *d_ptr; /// points to the definition in the Entry int tempWLen; /// length of the temp word string int tempDLen; /// length of the temp def string char tempLine[INPUT_LINE_MAX_LEN] = {NIL}; /// stores a single line from the file // EXECUTE // getline(dataFile, tempLine) // get a "word,def" line from the file dataFile.getline(tempLine, INPUT_LINE_MAX_LEN); // get a "word,def" line from the file // Parse the string tempW_ptr = tempLine; // point the temp word pointer at the first char in the line tempD_ptr = strchr(tempLine, COMMA); // point the def pointer at the comma *tempD_ptr = NIL; // replace the comma with a NIL ++tempD_ptr; // increment the temp def pointer // find the string lengths... +1 to account for terminator tempWLen = strlen(tempW_ptr) + 1; tempDLen = strlen(tempD_ptr) + 1; // Allocate heap memory for the term and defnition w_ptr = new char[ tempWLen ]; d_ptr = new char[ tempDLen ]; // check memory allocation if( !w_ptr && !d_ptr ) { cout << MEM_ERR_MSG << endl; exit(EXIT_FAILURE); } // copy the temp word, def into the newly allocated memory and terminate the strings strcpy(w_ptr,tempW_ptr); w_ptr[tempWLen] = NIL; strcpy(d_ptr,tempD_ptr); d_ptr[tempDLen] = NIL; // set the pointers for the entry objects m_DictEntry_ptr[ EntryIdx ].setWordPtr(w_ptr); m_DictEntry_ptr[ EntryIdx ].setDefPtr(d_ptr); } // close the file dataFile.close(); } else { cout << ENTER << FILE_ERR_MSG << endl; exit(EXIT_FAILURE); } } /** * cleans up dynamic memory */ Dictionary::~Dictionary() { delete[] m_DictEntry_ptr; /// thou shalt not have memory leaks. } /** * Looks up definition */ /* const char *lookupDefinition( const char *word ) { // print out the word ---- definition } */ /** * prints out the entire dictionary in sorted order */ /* void forEach( WordDefFunc func ) { // to sort before or now.... that is the question } */ Entry.h/cpp #ifndef ENTRY_H #define ENTRY_H // /////////////////////////////////////////////////////////////////////////////////// // INCLUDES (C++ Std lib) #include <cstdlib> /// EXIT_SUCCESS, NULL // /////////////////////////////////////////////////////////////////////////////////// // PRE-PROCESSOR MACROS #define NIL '\0' /// C-String terminator #define MEM_ERR_MSG "Memory allocation has failed. Program will now terminate." // /////////////////////////////////////////////////////////////////////////////////// // CLASS DEFINITION class Entry { public: Entry(void) : m_word_ptr(NULL), m_def_ptr(NULL) { /* default constructor */ }; void setWordPtr(char *w_ptr); /// sets the pointer to the word - only if the pointer is empty void setDefPtr(char *d_ptr); /// sets the ponter to the definition - only if the pointer is empty /// returns what is pointed to by the word pointer char getWord(void) const { return *m_word_ptr; } /// returns what is pointed to by the definition pointer char getDef(void) const { return *m_def_ptr; } private: char *m_word_ptr; /** points to a dictionary word */ char *m_def_ptr; /** points to a dictionary definition */ }; #endif -------------------------------------------------- // /////////////////////////////////////////////////////////////////////////////////// // DEPENDENCIES (custom header files) #include "entry.h" /// class header file // /////////////////////////////////////////////////////////////////////////////////// // PUBLIC FUNCTIONS /* * only change the word member var if it is in its initial state */ void Entry::setWordPtr(char *w_ptr) { if(m_word_ptr == NULL) { m_word_ptr = w_ptr; } } /* * only change the def member var if it is in its initial state */ void Entry::setDefPtr(char *d_ptr) { if(m_def_ptr == NULL) { m_word_ptr = d_ptr; } }

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• Having trouble with instantiating objects in PHP & Ajax custom shopping cart

  - by Phil

  This is my first time playing with both ajax and objects, so please go easy on me I have 3 pages that make up the tester shopping cart. 1) page with 'add' 'remove' buttons and ajax code to call the PHP functions on page 2. this is the actual user page with the HTML output. 2) page with PHP cart function calls, receives $_GET requests from ajax on page 1 and calls functions of the cart object from page 3, returns results to page 1. 3) page with cart object definition. Here's the problem I believe I'm having. Currently I have 'session_start()' on pgs 1 & 2, and the cart definition (pag 3) on pgs 1 & 2. I only define '$_SESSION[cart]= new Cart' on page 2. However, it seems like each time i hit an ajax function (eg each time pg 2 reloads) it seems like it's rewriting $_SESSION['cart'] over again, thus it's always empty at each new click (even tho it displays results of that click) However, if i don't define '$_SESSION[cart] = new Cart' on pg 2, i get an error: Fatal error: main() [function.main]: The script tried to execute a method or access a property of an incomplete object. Please ensure that the class definition "Cart" of the object you are trying to operate on was loaded before unserialize() gets called or provide a __autoload() function to load the class definition in /home3/foundloc/public_html/booka/carti.php on line 17 Any suggestions? How can i stop re-creating my cart each time my page 2 (php cart function page) is called by ajax?

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• What is the recommended coding style for PowerShell?

  - by stej

  Is there any recommended coding style how to write PowerShell scripts? It's not about how to structure the code (how many functions, if to use module, ...). It's about 'how to write the code so that it is readable'. In programming languages there are some recommended coding styles (what to indent, how to indent - spaces/tabs, where to make new line, where to put braces,...), but I haven't seen any suggestion for PowerShell. What I'm interested particularly in: How to write parameters function New-XYZItem ( [string] $ItemName , [scriptblock] $definition ) { ... (I see that it's more like 'V1' syntax) or function New-PSClass { param([string] $ClassName ,[scriptblock] $definition )... or (why to add empty attribute?) function New-PSClass { param([Parameter()][string] $ClassName ,[Parameter()][scriptblock] $definition )... or (other formatting I saw maybe in Jaykul's code) function New-PSClass { param( [Parameter()] [string] $ClassName , [Parameter()] [scriptblock] $definition )... or ..? How to write complex pipeline Get-SomeData -param1 abc -param2 xyz | % { $temp1 = $_ 1..100 | % { Process-somehow $temp1 $_ } } | % { Process-Again $_ } | Sort-Object -desc or (name of cmdlet on new line) Get-SomeData -param1 abc -param2 xyz | % { $temp1 = $_ 1..100 | % { Process-somehow $temp1 $_ } } | % { Process-Again $_ } | Sort-Object -desc | and what if there are -begin -process -end params? how to make it the most readable? Get-SomeData -param1 abc -param2 xyz | % -begin { init } -process { Process-somehow2 ... } -end { Process-somehow3 ... } | % -begin { } .... or Get-SomeData -param1 abc -param2 xyz | % ` -begin { init } ` -process { Process-somehow2 ... } ` -end { Process-somehow3 ... } | % -begin { } .... the indentitation is important here and what element is put on new line as well. I have covered only questions that come on my mind very frequently. There are some others, but I'd like to keep this SO question 'short'. Any other suggestions are welcome.

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• Setting up multiple channel types (AMF/AMFX) for Flex/BlazeDs

  - by Fergal

  We've configured our Flex client to have two channels for calling our services via BlazeDS. One channel is configured to use AMFChannel and the other for HTTPChannel. Here's the services-config.xml <channel-definition id="my-amf" class="mx.messaging.channels.AMFChannel"> <endpoint url="http://{server.name}:{server.port}/{context.root}/data/messagebroker/amf" class="flex.messaging.endpoints.AMFEndpoint" /> <properties> <polling-enabled>false</polling-enabled> </properties> </channel-definition> <channel-definition id="my-amfx" class="mx.messaging.channels.HTTPChannel"> <endpoint url="http://{server.name}:{server.port}/{context.root}/data/messagebroker/amfx" class="flex.messaging.endpoints.HTTPEndpoint" /> <properties> <polling-enabled>false</polling-enabled> </properties> </channel-definition> Our flex client is written to use either AMF or AMFX depending on how we configure it. The problem is that although the client can switch between channels it sends an AMF binary payload when attempting to call services via AMFX (expecting XML). The funny thing is that we can write services-config.xml to use either AMF or AMFX individually but Flex doesn't seem to want to let us use both. Is this a bug in Flex? If not how can we get it to use the correct protocol?

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• Django User M2M relationship

  - by Antonio

  When trying to syncdb with the following models: class Contact(models.Model): user_from = models.ForeignKey(User,related_name='from_user') user_to = models.ForeignKey(User, related_name='to_user') class Meta: unique_together = (('user_from', 'user_to'),) User.add_to_class('following', models.ManyToManyField('self', through=Contact, related_name='followers', symmetrical=False)) I get the following error: Error: One or more models did not validate: auth.user: Accessor for m2m field 'following' clashes with related m2m field 'User.followers'. Add a related_name argument to the definition for 'following'. auth.user: Reverse query name for m2m field 'following' clashes with related m2m field 'User.followers'. Add a related_name argument to the definition for 'following'. auth.user: The model User has two manually-defined m2m relations through the model Contact, which is not permitted. Please consider using an extra field on your intermediary model instead. auth.user: Accessor for m2m field 'following' clashes with related m2m field 'User.followers'. Add a related_name argument to the definition for 'following'. auth.user: Reverse query name for m2m field 'following' clashes with related m2m field 'User.followers'. Add a related_name argument to the definition for 'following'.

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• Creating circular generic references

  - by M. Jessup

  I am writing an application to do some distributed calculations in a peer to peer network. In defining the network I have two class the P2PNetwork and P2PClient. I want these to be generic and so have the definitions of: P2PNetwork<T extends P2PClient<? extends P2PNetwork<T>>> P2PClient<T extends P2PNetwork<? extends T>> with P2PClient defining a method of setNetwork(T network). What I am hoping to describe with this code is: A P2PNetwork is constituted of clients of a certain type A P2PClient may only belong to a network whose clients consist of the same type as this client (the circular-reference) This seems correct to me but if I try to create a non-generic version such as MyP2PClient<MyP2PNetwork<? extends MyP2PClient>> myClient; and other variants I receive numerous errors from the compiler. So my questions are as follows: Is a generic circular reference even possible (I have never seen anything explicitly forbidding it)? Is the above generic definition a correct definition of such a circular relationship? If it is valid, is it the "correct" way to describe such a relationship (i.e. is there another valid definition, which is stylistically preferred)? How would I properly define a non-generic instance of a Client and Server given the proper generic definition?

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• Why this Either-monad code does not type check?

  - by pf_miles

  instance Monad (Either a) where return = Left fail = Right Left x >>= f = f x Right x >>= _ = Right x this code frag in 'baby.hs' caused the horrible compilation error: Prelude> :l baby [1 of 1] Compiling Main ( baby.hs, interpreted ) baby.hs:2:18: Couldn't match expected type `a1' against inferred type `a' `a1' is a rigid type variable bound by the type signature for `return' at <no location info> `a' is a rigid type variable bound by the instance declaration at baby.hs:1:23 In the expression: Left In the definition of `return': return = Left In the instance declaration for `Monad (Either a)' baby.hs:3:16: Couldn't match expected type `[Char]' against inferred type `a1' `a1' is a rigid type variable bound by the type signature for `fail' at <no location info> Expected type: String Inferred type: a1 In the expression: Right In the definition of `fail': fail = Right baby.hs:4:26: Couldn't match expected type `a1' against inferred type `a' `a1' is a rigid type variable bound by the type signature for `>>=' at <no location info> `a' is a rigid type variable bound by the instance declaration at baby.hs:1:23 In the first argument of `f', namely `x' In the expression: f x In the definition of `>>=': Left x >>= f = f x baby.hs:5:31: Couldn't match expected type `b' against inferred type `a' `b' is a rigid type variable bound by the type signature for `>>=' at <no location info> `a' is a rigid type variable bound by the instance declaration at baby.hs:1:23 In the first argument of `Right', namely `x' In the expression: Right x In the definition of `>>=': Right x >>= _ = Right x Failed, modules loaded: none. why this happen? and how could I make this code compile ? thanks for any help~

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• Struts2 Tiles in Google app engine

  - by user365941

  I am trying to build an java web application using struts2 and tiles in Google App Engine. Below is my tiles.xml file <!DOCTYPE tiles-definitions PUBLIC "-//Apache Software Foundation//DTD Tiles Configuration 2.0//EN" "http://tiles.apache.org/dtds/tiles-config_2_0.dtd"> <tiles-definitions> <definition name="baseLayout" template="BaseLayout.jsp"> <put-attribute name="title" value="" /> <put-attribute name="header" value="Header.jsp" /> <put-attribute name="body" value="" /> <put-attribute name="footer" value="Footer.jsp" /> </definition> <definition name="/welcome.tiles" extends="baseLayout"> <put-attribute name="title" value="Welcome" /> <put-attribute name="body" value="Welcome.jsp" /> </definition> </tiles-definitions> But when I run the app,I am not getting any error. it just prints "Header.jsp Welcome.jsp Footer.jsp". It does not show the actual jsp pages. Please advise on what needs to be done. Thanks in advance Regards

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• Cyclic Reference - protocols and subclasses

  - by blindJesse

  I'm getting some cyclic reference (I think) problems between a few classes that require imported headers due to either subclassing or protocol definitions. I can explain why things are set up this way but I'm not sure it's essential. Basically these classes are managing reciprocal to-many data relationships. The layout is this: Class A imports Class B because it's a delegate of Class B and needs its protocol definition. Class B imports Class C because it's a subclass of Class C. Class C imports Class A because it's a delegate of Class A and needs its protocol definition. Here's some sample code that illustrates the problem. The errors I'm getting are as follows: In Class A - "Can't find protocol definition for Class_B_Delegate". In Class B - "Can't find interface declaration for Class C - superclass of Class B." In Class C - "Can't find protocol definition for Class_A_Delegate". Class A header: #import <Foundation/Foundation.h> #import "Class_B.h" @protocol Class_A_Delegate @end @interface Class_A : NSObject <Class_B_Delegate> { } @end Class B header: #import <Foundation/Foundation.h> #import "Class_C.h" @protocol Class_B_Delegate <NSObject> @end @interface Class_B : Class_C { } @end Class C Header: #import <Foundation/Foundation.h> #import "Class_A.h" @interface Class_C : NSObject <Class_A_Delegate> { } @end

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• Android, how to use DexClassLoader to dynamically replace an Activity or Service

  - by RickNotFred

  I am trying to do something similar to this stackoverflow posting. What I want to do is to read the definition of an activity or service from the SD card. To avoid manifest permission issues, I create a shell version of this activity in the .apk, but try to replace it with an activity of the same name residing on the SD card at run time. Unfortunately, I am able to load the activity class definition from the SD card using DexClassLoader, but the original class definition is the one that is executed. Is there a way to specify that the new class definition replaces the old one, or any suggestions on avoiding the manifest permission issues without actually providing the needed activity in the package? The code sample: ClassLoader cl = new DexClassLoader("/sdcard/mypath/My.apk", getFilesDir().getAbsolutePath(), null, MainActivity.class.getClassLoader()); try { Class<?> c = cl.loadClass("com.android.my.path.to.a.loaded.activity"); Intent i = new Intent(getBaseContext(), c); startActivity(i); } catch (Exception e) { Intead of launching the com.android.my.path.to.a.loaded.activity specified in /sdcard/mypath/My.apk, it launches the activity statically loaded into the project.

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• c++ function scope

  - by Myx

  I have a main function in A.cpp which has the following relevant two lines of code: B definition(input_file); definition.Print(); In B.h I have the following relevant lines of code: class B { public: // Constructors B(void); B(const char *filename); ~B(void); // File input int ParseLSFile(const char *filename); // Debugging void Print(void); // Data int var1; double var2; vector<char* > var3; map<char*, vector<char* > > var4; } In B.cpp, I have the following function signatures (sorry for being redundant): B::B(void) : var1(-1), var2(numeric_limits<double>::infinity()) { } B::B(const char *filename) { B *def = new B(); def->ParseLSFile(filename); } B::~B(void) { // Free memory for var3 and var 4 } int B::ParseLSFile(const char *filename) { // assign var1, var2, var3, and var4 values } void B::Print(void) { // print contents of var1, var2, var3, and var4 to stdout } So when I call Print() from within B::ParseLSFile(...), then the contents of my structures print correctly to stdout. However, when I call definition.Print() from A.cpp, my structures are empty or contain garbage. Can anyone recommend the correct way to initialize/pass my structures so that I can access them outside of the scope of my function definition? Thanks.

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• Using StructureMap to create classes by a name?

  - by Bevan

  How can I use StructureMap to resolve to an appropriate implementation of an interface based on a name stored in an attribute? In my project, I have many different kinds of widgets, each descending from IWidget, and each decorated with an attribute specifying the kind of associated element. To illustrate: [Configuration("header")] public class HeaderWidget : IWidget { } [Configuration("linegraph")] public class LineGraphWidget : IWidget { } When processing my (XML) configuration file, I want to obtain an instance of the appropriate concrete class based on the name of the element I'm processing. public IWidget CreateWidget(XElement definition) { var kind = definition.Name.LocalName; var widget = // What goes here? widget.Configure(definition); return widget; } Each definition should result in a different widget being created - I don't need or want the instances to be shared. In the past I've written plenty of code to do this kind of thing manually, including writing a custom "roll-your-own" IoC container for one project. However, one of my goals with this project is to become proficient with StructureMap instead of reinventing the wheel. I think I've already managed to set up automatic scanning of assemblies so that StructureMap knows about all my IWidget implementations: public class WidgetRegistration : Registry { public WidgetRegistration() { Scan( scanner => { scanner.AssembliesFromApplicationBaseDirectory(); scanner.AddAllTypesOf<IWidget>(); }); } } However, this isn't registering the names of my widgets with StructureMap. What do I need to add to make my scenario work? (While I am trying to use StructureMap in this project, an answer showing me how to solve this problem with a different DI/IoC tool would still be valuable.)

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• Type errors when using same name

  - by lykimq

  I have 3 files: 1) cpf0.ml type string = char list type url = string type var = string type name = string type symbol = | Symbol_name of name 2) problem.ml: type symbol = | Ident of string 3) test.ml open Problem;; open Cpf0;; let symbol b = function | Symbol_name n -> Ident n When I combine test.ml: ocamlc -c test.ml. I received an error: This expression has type Cpf0.name = char list but an expression was expected of type string Could you please help me to correct it? Thank you very much EDIT: Thank you for your answer. I want to explain more about these 3 files: Because I am working with extraction in Coq to Ocaml type: cpf0.ml is generated from cpf.v : Require Import String. Definition string := string. Definition name := string. Inductive symbol := | Symbol_name : name -> symbol. The code extraction.v: Set Extraction Optimize. Extraction Language Ocaml. Require ExtrOcamlBasic ExtrOcamlString. Extraction Blacklist cpf list. where ExtrOcamlString I opened: open Cpf0;; in problem.ml, and I got a new problem because in problem.ml they have another definition for type string This expression has type Cpf0.string = char list but an expression was expected of type Util.StrSet.elt = string Here is a definition in util.ml defined type string: module Str = struct type t = string end;; module StrOrd = Ord.Make (Str);; module StrSet = Set.Make (StrOrd);; module StrMap = Map.Make (StrOrd);; let set_add_chk x s = if StrSet.mem x s then failwith (x ^ " already declared") else StrSet.add x s;; I was trying to change t = string to t = char list, but if I do that I have to change a lot of function it depend on (for example: set_add_chk above). Could you please give me a good idea? how I would do in this case.

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• How to handle build rule with unknown targets in OMake when target list generator is built

  - by Michael E

  I have a project which uses OMake for its build system, and I am trying to handle a rather tough corner case. I have some definition files and a tool which can take these definition files and create GraphViz files. There are two problems, though: Each definition file can produce multiple graphs, and the list of graphs it can produce is encoded in the file. My dump tool does have a -list option which lists all the graphs a definition file will produce. This dump tool is built in the source tree. I want this list available in the OMakefile so I can use other rules to convert the DOT files to SVG, and have a phony target depend on all the SVGs (goal: a single build command which builds SVG descriptions of all my graphs). If I only had the first problem, it would be easy - I would run the tool to build a list, and then use that list to build a target which invokes the dumper to output the GraphViz files. However, I am rather stuck on forcing the dump tool to be built before it is needed. If this were make, I would just run make recursively to build the dump tool. OMake does not allow recursive invocation, however, and the build function is only usable from osh. Any suggestions for a good solution to this problem?

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• Grab two parts of a single, short string

  - by TankorSmash

  I'm looking to fill a python dict with TAG:definition pairs, and I'm using RegExr http://gskinner.com/RegExr/ to write the regex My first step is to parse a line, from http://www.id3.org/id3v2.3.0, or http://pastebin.com/VJEBGauL and pull out the ID3 tag and the associated definition. For example the first line: 4.20 AENC [#sec4.20 Audio encryption] would look like this myDict = {'AENC' : 'Audio encryption'} To grab the tag name, I've got it looking for at least 3 spaces, then 4 characters, then 4 spaces: {3}[a-zA-Z0-9]{4} {4} That part is easy enough. The second part, the definition, is not working out for me. So far, I've got (?<=(\[#.+?)) A Which should find, but not include the [# as well as an indeterminded set of characters until it finds: _A, but it's failing. If I remove .+? and replace _A with s it works out alright. What is going wrong? *The underscores represent spaces, which don't show up on SO. How do I grab the definition, ie,(Audio encryption) of the ID3v2 tag from the line, using RegEx?

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• A simple Dynamic Proxy

  - by Abhijeet Patel

  Frameworks such as EF4 and MOQ do what most developers consider "dark magic". For instance in EF4, when you use a POCO for an entity you can opt-in to get behaviors such as "lazy-loading" and "change tracking" at runtime merely by ensuring that your type has the following characteristics: The class must be public and not sealed. The class must have a public or protected parameter-less constructor. The class must have public or protected properties Adhere to this and your type is magically endowed with these behaviors without any additional programming on your part. Behind the scenes the framework subclasses your type at runtime and creates a "dynamic proxy" which has these additional behaviors and when you navigate properties of your POCO, the framework replaces the POCO type with derived type instances. The MOQ framework does simlar magic. Let's say you have a simple interface:   public interface IFoo      {          int GetNum();      }   We can verify that the GetNum() was invoked on a mock like so:   var mock = new Mock<IFoo>(MockBehavior.Default);   mock.Setup(f => f.GetNum());   var num = mock.Object.GetNum();   mock.Verify(f => f.GetNum());   Beind the scenes the MOQ framework is generating a dynamic proxy by implementing IFoo at runtime. the call to moq.Object returns the dynamic proxy on which we then call "GetNum" and then verify that this method was invoked. No dark magic at all, just clever programming is what's going on here, just not visible and hence appears magical! Let's create a simple dynamic proxy generator which accepts an interface type and dynamically creates a proxy implementing the interface type specified at runtime.     public static class DynamicProxyGenerator   {       public static T GetInstanceFor<T>()       {           Type typeOfT = typeof(T);           var methodInfos = typeOfT.GetMethods();           AssemblyName assName = new AssemblyName("testAssembly");           var assBuilder = AppDomain.CurrentDomain.DefineDynamicAssembly(assName, AssemblyBuilderAccess.RunAndSave);           var moduleBuilder = assBuilder.DefineDynamicModule("testModule", "test.dll");           var typeBuilder = moduleBuilder.DefineType(typeOfT.Name + "Proxy", TypeAttributes.Public);              typeBuilder.AddInterfaceImplementation(typeOfT);           var ctorBuilder = typeBuilder.DefineConstructor(                     MethodAttributes.Public,                     CallingConventions.Standard,                     new Type[] { });           var ilGenerator = ctorBuilder.GetILGenerator();           ilGenerator.EmitWriteLine("Creating Proxy instance");           ilGenerator.Emit(OpCodes.Ret);           foreach (var methodInfo in methodInfos)           {               var methodBuilder = typeBuilder.DefineMethod(                   methodInfo.Name,                   MethodAttributes.Public | MethodAttributes.Virtual,                   methodInfo.ReturnType,                   methodInfo.GetParameters().Select(p => p.GetType()).ToArray()                   );               var methodILGen = methodBuilder.GetILGenerator();               methodILGen.EmitWriteLine("I'm a proxy");               if (methodInfo.ReturnType == typeof(void))               {                   methodILGen.Emit(OpCodes.Ret);               }               else               {                   if (methodInfo.ReturnType.IsValueType || methodInfo.ReturnType.IsEnum)                   {                       MethodInfo getMethod = typeof(Activator).GetMethod(/span>"CreateInstance",new Type[]{typeof((Type)});                                               LocalBuilder lb = methodILGen.DeclareLocal(methodInfo.ReturnType);                       methodILGen.Emit(OpCodes.Ldtoken, lb.LocalType);                       methodILGen.Emit(OpCodes.Call, typeofype).GetMethod("GetTypeFromHandle"));  ));                       methodILGen.Emit(OpCodes.Callvirt, getMethod);                       methodILGen.Emit(OpCodes.Unbox_Any, lb.LocalType);                                                              }                 else                   {                       methodILGen.Emit(OpCodes.Ldnull);                   }                   methodILGen.Emit(OpCodes.Ret);               }               typeBuilder.DefineMethodOverride(methodBuilder, methodInfo);           }                     Type constructedType = typeBuilder.CreateType();           var instance = Activator.CreateInstance(constructedType);           return (T)instance;       }   }   Dynamic proxies are created by calling into the following main types: AssemblyBuilder, TypeBuilder, Modulebuilder and ILGenerator. These types enable dynamically creating an assembly and emitting .NET modules and types in that assembly, all using IL instructions. Let's break down the code above a bit and examine it piece by piece                Type typeOfT = typeof(T);              var methodInfos = typeOfT.GetMethods();              AssemblyName assName = new AssemblyName("testAssembly");              var assBuilder = AppDomain.CurrentDomain.DefineDynamicAssembly(assName, AssemblyBuilderAccess.RunAndSave);              var moduleBuilder = assBuilder.DefineDynamicModule("testModule", "test.dll");              var typeBuilder = moduleBuilder.DefineType(typeOfT.Name + "Proxy", TypeAttributes.Public);   We are instructing the runtime to create an assembly caled "test.dll"and in this assembly we then emit a new module called "testModule". We then emit a new type definition of name "typeName"Proxy into this new module. This is the definition for the "dynamic proxy" for type T                 typeBuilder.AddInterfaceImplementation(typeOfT);               var ctorBuilder = typeBuilder.DefineConstructor(                         MethodAttributes.Public,                         CallingConventions.Standard,                         new Type[] { });               var ilGenerator = ctorBuilder.GetILGenerator();               ilGenerator.EmitWriteLine("Creating Proxy instance");               ilGenerator.Emit(OpCodes.Ret);   The newly created type implements type T and defines a default parameterless constructor in which we emit a call to Console.WriteLine. This call is not necessary but we do this so that we can see first hand that when the proxy is constructed, when our default constructor is invoked.   var methodBuilder = typeBuilder.DefineMethod(                      methodInfo.Name,                      MethodAttributes.Public | MethodAttributes.Virtual,                      methodInfo.ReturnType,                      methodInfo.GetParameters().Select(p => p.GetType()).ToArray()                      );   We then iterate over each method declared on type T and add a method definition of the same name into our "dynamic proxy" definition     if (methodInfo.ReturnType == typeof(void))   {       methodILGen.Emit(OpCodes.Ret);   }   If the return type specified in the method declaration of T is void we simply return.     if (methodInfo.ReturnType.IsValueType || methodInfo.ReturnType.IsEnum)   {                               MethodInfo getMethod = typeof(Activator).GetMethod("CreateInstance",                                                         new Type[]{typeof(Type)});                               LocalBuilder lb = methodILGen.DeclareLocal(methodInfo.ReturnType);                                                     methodILGen.Emit(OpCodes.Ldtoken, lb.LocalType);       methodILGen.Emit(OpCodes.Call, typeof(Type).GetMethod("GetTypeFromHandle"));       methodILGen.Emit(OpCodes.Callvirt, getMethod);       methodILGen.Emit(OpCodes.Unbox_Any, lb.LocalType);   }   If the return type in the method declaration of T is either a value type or an enum, then we need to create an instance of the value type and return that instance the caller. In order to accomplish that we need to do the following: 1) Get a handle to the Activator.CreateInstance method 2) Declare a local variable which represents the Type of the return type(i.e the type object of the return type) specified on the method declaration of T(obtained from the MethodInfo) and push this Type object onto the evaluation stack. In reality a RuntimeTypeHandle is what is pushed onto the stack. 3) Invoke the "GetTypeFromHandle" method(a static method in the Type class) passing in the RuntimeTypeHandle pushed onto the stack previously as an argument, the result of this invocation is a Type object (representing the method's return type) which is pushed onto the top of the evaluation stack. 4) Invoke Activator.CreateInstance passing in the Type object from step 3, the result of this invocation is an instance of the value type boxed as a reference type and pushed onto the top of the evaluation stack. 5) Unbox the result and place it into the local variable of the return type defined in step 2   methodILGen.Emit(OpCodes.Ldnull);   If the return type is a reference type then we just load a null onto the evaluation stack   methodILGen.Emit(OpCodes.Ret);   Emit a a return statement to return whatever is on top of the evaluation stack(null or an instance of a value type) back to the caller     Type constructedType = typeBuilder.CreateType();   var instance = Activator.CreateInstance(constructedType);   return (T)instance;   Now that we have a definition of the "dynamic proxy" implementing all the methods declared on T, we can now create an instance of the proxy type and return that out typed as T. The caller can now invoke the generator and request a dynamic proxy for any type T. In our example when the client invokes GetNum() we get back "0". Lets add a new method on the interface called DayOfWeek GetDay()   public interface IFoo      {          int GetNum();          DayOfWeek GetDay();      }   When GetDay() is invoked, the "dynamic proxy" returns "Sunday" since that is the default value for the DayOfWeek enum This is a very trivial example of dynammic proxies, frameworks like MOQ have a way more sophisticated implementation of this paradigm where in you can instruct the framework to create proxies which return specified values for a method implementation.

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• Curing the Database-Application mismatch

  - by Phil Factor

  If an application requires access to a database, then you have to be able to deploy it so as to be version-compatible with the database, in phase. If you can deploy both together, then the application and database must normally be deployed at the same version in which they, together, passed integration and functional testing.  When a single database supports more than one application, then the problem gets more interesting. I’ll need to be more precise here. It is actually the application-interface definition of the database that needs to be in a compatible ‘version’.  Most databases that get into production have no separate application-interface; in other words they are ‘close-coupled’.  For this vast majority, the whole database is the application-interface, and applications are free to wander through the bowels of the database scot-free.  If you’ve spurned the perceived wisdom of application architects to have a defined application-interface within the database that is based on views and stored procedures, any version-mismatch will be as sensitive as a kitten.  A team that creates an application that makes direct access to base tables in a database will have to put a lot of energy into keeping Database and Application in sync, to say nothing of having to tackle issues such as security and audit. It is not the obvious route to development nirvana. I’ve been in countless tense meetings with application developers who initially bridle instinctively at the apparent restrictions of being ‘banned’ from the base tables or routines of a database.  There is no good technical reason for needing that sort of access that I’ve ever come across.  Everything that the application wants can be delivered via a set of views and procedures, and with far less pain for all concerned: This is the application-interface.  If more than zero developers are creating a database-driven application, then the project will benefit from the loose-coupling that an application interface brings. What is important here is that the database development role is separated from the application development role, even if it is the same developer performing both roles. The idea of an application-interface with a database is as old as I can remember. The big corporate or government databases generally supported several applications, and there was little option. When a new application wanted access to an existing corporate database, the developers, and myself as technical architect, would have to meet with hatchet-faced DBAs and production staff to work out an interface. Sure, they would talk up the effort involved for budgetary reasons, but it was routine work, because it decoupled the database from its supporting applications. We’d be given our own stored procedures. One of them, I still remember, had ninety-two parameters. All database access was encapsulated in one application-module. If you have a stable defined application-interface with the database (Yes, one for each application usually) you need to keep the external definitions of the components of this interface in version control, linked with the application source,  and carefully track and negotiate any changes between database developers and application developers.  Essentially, the application development team owns the interface definition, and the onus is on the Database developers to implement it and maintain it, in conformance.  Internally, the database can then make all sorts of changes and refactoring, as long as source control is maintained.  If the application interface passes all the comprehensive integration and functional tests for the particular version they were designed for, nothing is broken. Your performance-testing can ‘hang’ on the same interface, since databases are judged on the performance of the application, not an ‘internal’ database process. The database developers have responsibility for maintaining the application-interface, but not its definition,  as they refactor the database. This is easily tested on a daily basis since the tests are normally automated. In this setting, the deployment can proceed if the more stable application-interface, rather than the continuously-changing database, passes all tests for the version of the application. Normally, if all goes well, a database with a well-designed application interface can evolve gracefully without changing the external appearance of the interface, and this is confirmed by integration tests that check the interface, and which hopefully don’t need to be altered at all often.  If the application is rapidly changing its ‘domain model’  in the light of an increased understanding of the application domain, then it can change the interface definitions and the database developers need only implement the interface rather than refactor the underlying database.  The test team will also have to redo the functional and integration tests which are, of course ‘written to’ the definition.  The Database developers will find it easier if these tests are done before their re-wiring  job to implement the new interface. If, at the other extreme, an application receives no further development work but survives unchanged, the database can continue to change and develop to keep pace with the requirements of the other applications it supports, and needs only to take care that the application interface is never broken. Testing is easy since your automated scripts to test the interface do not need to change. The database developers will, of course, maintain their own source control for the database, and will be likely to maintain versions for all major releases. However, this will not need to be shared with the applications that the database servers. On the other hand, the definition of the application interfaces should be within the application source. Changes in it have to be subject to change-control procedures, as they will require a chain of tests. Once you allow, instead of an application-interface, an intimate relationship between application and database, we are in the realms of impedance mismatch, over and above the obvious security problems.  Part of this impedance problem is a difference in development practices. Whereas the application has to be regularly built and integrated, this isn’t necessarily the case with the database.  An RDBMS is inherently multi-user and self-integrating. If the developers work together on the database, then a subsequent integration of the database on a staging server doesn’t often bring nasty surprises. A separate database-integration process is only needed if the database is deliberately built in a way that mimics the application development process, but which hampers the normal database-development techniques.  This process is like demanding a official walking with a red flag in front of a motor car.  In order to closely coordinate databases with applications, entire databases have to be ‘versioned’, so that an application version can be matched with a database version to produce a working build without errors.  There is no natural process to ‘version’ databases.  Each development project will have to define a system for maintaining the version level. A curious paradox occurs in development when there is no formal application-interface. When the strains and cracks happen, the extra meetings, bureaucracy, and activity required to maintain accurate deployments looks to IT management like work. They see activity, and it looks good. Work means progress.  Management then smile on the design choices made. In IT, good design work doesn’t necessarily look good, and vice versa.

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• AngularJS on top of ASP.NET: Moving the MVC framework out to the browser

  - by Varun Chatterji

  Heavily drawing inspiration from Ruby on Rails, MVC4’s convention over configuration model of development soon became the Holy Grail of .NET web development. The MVC model brought with it the goodness of proper separation of concerns between business logic, data, and the presentation logic. However, the MVC paradigm, was still one in which server side .NET code could be mixed with presentation code. The Razor templating engine, though cleaner than its predecessors, still encouraged and allowed you to mix .NET server side code with presentation logic. Thus, for example, if the developer required a certain <div> tag to be shown if a particular variable ShowDiv was true in the View’s model, the code could look like the following: Fig 1: To show a div or not. Server side .NET code is used in the View Mixing .NET code with HTML in views can soon get very messy. Wouldn’t it be nice if the presentation layer (HTML) could be pure HTML? Also, in the ASP.NET MVC model, some of the business logic invariably resides in the controller. It is tempting to use an anti­pattern like the one shown above to control whether a div should be shown or not. However, best practice would indicate that the Controller should not be aware of the div. The ShowDiv variable in the model should not exist. A controller should ideally, only be used to do the plumbing of getting the data populated in the model and nothing else. The view (ideally pure HTML) should render the presentation layer based on the model. In this article we will see how Angular JS, a new JavaScript framework by Google can be used effectively to build web applications where: 1. Views are pure HTML 2. Controllers (in the server sense) are pure REST based API calls 3. The presentation layer is loaded as needed from partial HTML only files. What is MVVM? MVVM short for Model View View Model is a new paradigm in web development. In this paradigm, the Model and View stuff exists on the client side through javascript instead of being processed on the server through postbacks. These frameworks are JavaScript frameworks that facilitate the clear separation of the “frontend” or the data rendering logic from the “backend” which is typically just a REST based API that loads and processes data through a resource model. The frameworks are called MVVM as a change to the Model (through javascript) gets reflected in the view immediately i.e. Model > View. Also, a change on the view (through manual input) gets reflected in the model immediately i.e. View > Model. The following figure shows this conceptually (comments are shown in red): Fig 2: Demonstration of MVVM in action In Fig 2, two text boxes are bound to the same variable model.myInt. Thus, changing the view manually (changing one text box through keyboard input) also changes the other textbox in real time demonstrating V > M property of a MVVM framework. Furthermore, clicking the button adds 1 to the value of model.myInt thus changing the model through JavaScript. This immediately updates the view (the value in the two textboxes) thus demonstrating the M > V property of a MVVM framework. Thus we see that the model in a MVVM JavaScript framework can be regarded as “the single source of truth“. This is an important concept. Angular is one such MVVM framework. We shall use it to build a simple app that sends SMS messages to a particular number. Application, Routes, Views, Controllers, Scope and Models Angular can be used in many ways to construct web applications. For this article, we shall only focus on building Single Page Applications (SPAs). Many of the approaches we will follow in this article have alternatives. It is beyond the scope of this article to explain every nuance in detail but we shall try to touch upon the basic concepts and end up with a working application that can be used to send SMS messages using Sent.ly Plus (a service that is itself built using Angular). Before you read on, we would like to urge you to forget what you know about Models, Views, Controllers and Routes in the ASP.NET MVC4 framework. All these words have different meanings in the Angular world. Whenever these words are used in this article, they will refer to Angular concepts and not ASP.NET MVC4 concepts. The following figure shows the skeleton of the root page of an SPA: Fig 3: The skeleton of a SPA The skeleton of the application is based on the Bootstrap starter template which can be found at: http://getbootstrap.com/examples/starter­template/ Apart from loading the Angular, jQuery and Bootstrap JavaScript libraries, it also loads our custom scripts /app/js/controllers.js /app/js/app.js These scripts define the routes, views and controllers which we shall come to in a moment. Application Notice that the body tag (Fig. 3) has an extra attribute: ng­app=”smsApp” Providing this tag “bootstraps” our single page application. It tells Angular to load a “module” called smsApp. This “module” is defined /app/js/app.js angular.module('smsApp', ['smsApp.controllers', function () {}]) Fig 4: The definition of our application module The line shows above, declares a module called smsApp. It also declares that this module “depends” on another module called “smsApp.controllers”. The smsApp.controllers module will contain all the controllers for our SPA. Routing and Views Notice that in the Navbar (in Fig 3) we have included two hyperlinks to: “#/app” “#/help” This is how Angular handles routing. Since the URLs start with “#”, they are actually just bookmarks (and not server side resources). However, our route definition (in /app/js/app.js) gives these URLs a special meaning within the Angular framework. angular.module('smsApp', ['smsApp.controllers', function () { }]) //Configure the routes .config(['$routeProvider', function ($routeProvider) { $routeProvider.when('/binding', { templateUrl: '/app/partials/bindingexample.html', controller: 'BindingController' }); }]); Fig 5: The definition of a route with an associated partial view and controller As we can see from the previous code sample, we are using the $routeProvider object in the configuration of our smsApp module. Notice how the code “asks for” the $routeProvider object by specifying it as a dependency in the [] braces and then defining a function that accepts it as a parameter. This is known as dependency injection. Please refer to the following link if you want to delve into this topic: http://docs.angularjs.org/guide/di What the above code snippet is doing is that it is telling Angular that when the URL is “#/binding”, then it should load the HTML snippet (“partial view”) found at /app/partials/bindingexample.html. Also, for this URL, Angular should load the controller called “BindingController”. We have also marked the div with the class “container” (in Fig 3) with the ng­view attribute. This attribute tells Angular that views (partial HTML pages) defined in the routes will be loaded within this div. You can see that the Angular JavaScript framework, unlike many other frameworks, works purely by extending HTML tags and attributes. It also allows you to extend HTML with your own tags and attributes (through directives) if you so desire, you can find out more about directives at the following URL: http://www.codeproject.com/Articles/607873/Extending­HTML­with­AngularJS­Directives Controllers and Models We have seen how we define what views and controllers should be loaded for a particular route. Let us now consider how controllers are defined. Our controllers are defined in the file /app/js/controllers.js. The following snippet shows the definition of the “BindingController” which is loaded when we hit the URL http://localhost:port/index.html#/binding (as we have defined in the route earlier as shown in Fig 5). Remember that we had defined that our application module “smsApp” depends on the “smsApp.controllers” module (see Fig 4). The code snippet below shows how the “BindingController” defined in the route shown in Fig 5 is defined in the module smsApp.controllers: angular.module('smsApp.controllers', [function () { }]) .controller('BindingController', ['$scope', function ($scope) { $scope.model = {}; $scope.model.myInt = 6; $scope.addOne = function () { $scope.model.myInt++; } }]); Fig 6: The definition of a controller in the “smsApp.controllers” module. The pieces are falling in place! Remember Fig.2? That was the code of a partial view that was loaded within the container div of the skeleton SPA shown in Fig 3. The route definition shown in Fig 5 also defined that the controller called “BindingController” (shown in Fig 6.) was loaded when we loaded the URL: http://localhost:22544/index.html#/binding The button in Fig 2 was marked with the attribute ng­click=”addOne()” which added 1 to the value of model.myInt. In Fig 6, we can see that this function is actually defined in the “BindingController”. Scope We can see from Fig 6, that in the definition of “BindingController”, we defined a dependency on $scope and then, as usual, defined a function which “asks for” $scope as per the dependency injection pattern. So what is $scope? Any guesses? As you might have guessed a scope is a particular “address space” where variables and functions may be defined. This has a similar meaning to scope in a programming language like C#. Model: The Scope is not the Model It is tempting to assign variables in the scope directly. For example, we could have defined myInt as $scope.myInt = 6 in Fig 6 instead of $scope.model.myInt = 6. The reason why this is a bad idea is that scope in hierarchical in Angular. Thus if we were to define a controller which was defined within the another controller (nested controllers), then the inner controller would inherit the scope of the parent controller. This inheritance would follow JavaScript prototypal inheritance. Let’s say the parent controller defined a variable through $scope.myInt = 6. The child controller would inherit the scope through java prototypical inheritance. This basically means that the child scope has a variable myInt that points to the parent scopes myInt variable. Now if we assigned the value of myInt in the parent, the child scope would be updated with the same value as the child scope’s myInt variable points to the parent scope’s myInt variable. However, if we were to assign the value of the myInt variable in the child scope, then the link of that variable to the parent scope would be broken as the variable myInt in the child scope now points to the value 6 and not to the parent scope’s myInt variable. But, if we defined a variable model in the parent scope, then the child scope will also have a variable model that points to the model variable in the parent scope. Updating the value of $scope.model.myInt in the parent scope would change the model variable in the child scope too as the variable is pointed to the model variable in the parent scope. Now changing the value of $scope.model.myInt in the child scope would ALSO change the value in the parent scope. This is because the model reference in the child scope is pointed to the scope variable in the parent. We did no new assignment to the model variable in the child scope. We only changed an attribute of the model variable. Since the model variable (in the child scope) points to the model variable in the parent scope, we have successfully changed the value of myInt in the parent scope. Thus the value of $scope.model.myInt in the parent scope becomes the “single source of truth“. This is a tricky concept, thus it is considered good practice to NOT use scope inheritance. More info on prototypal inheritance in Angular can be found in the “JavaScript Prototypal Inheritance” section at the following URL: https://github.com/angular/angular.js/wiki/Understanding­Scopes. Building It: An Angular JS application using a .NET Web API Backend Now that we have a perspective on the basic components of an MVVM application built using Angular, let’s build something useful. We will build an application that can be used to send out SMS messages to a given phone number. The following diagram describes the architecture of the application we are going to build: Fig 7: Broad application architecture We are going to add an HTML Partial to our project. This partial will contain the form fields that will accept the phone number and message that needs to be sent as an SMS. It will also display all the messages that have previously been sent. All the executable code that is run on the occurrence of events (button clicks etc.) in the view resides in the controller. The controller interacts with the ASP.NET WebAPI to get a history of SMS messages, add a message etc. through a REST based API. For the purposes of simplicity, we will use an in memory data structure for the purposes of creating this application. Thus, the tasks ahead of us are: Creating the REST WebApi with GET, PUT, POST, DELETE methods. Creating the SmsView.html partial Creating the SmsController controller with methods that are called from the SmsView.html partial Add a new route that loads the controller and the partial. 1. Creating the REST WebAPI This is a simple task that should be quite straightforward to any .NET developer. The following listing shows our ApiController: public class SmsMessage { public string to { get; set; } public string message { get; set; } } public class SmsResource : SmsMessage { public int smsId { get; set; } } public class SmsResourceController : ApiController { public static Dictionary<int, SmsResource> messages = new Dictionary<int, SmsResource>(); public static int currentId = 0; // GET api/<controller> public List<SmsResource> Get() { List<SmsResource> result = new List<SmsResource>(); foreach (int key in messages.Keys) { result.Add(messages[key]); } return result; } // GET api/<controller>/5 public SmsResource Get(int id) { if (messages.ContainsKey(id)) return messages[id]; return null; } // POST api/<controller> public List<SmsResource> Post([FromBody] SmsMessage value) { //Synchronize on messages so we don't have id collisions lock (messages) { SmsResource res = (SmsResource) value; res.smsId = currentId++; messages.Add(res.smsId, res); //SentlyPlusSmsSender.SendMessage(value.to, value.message); return Get(); } } // PUT api/<controller>/5 public List<SmsResource> Put(int id, [FromBody] SmsMessage value) { //Synchronize on messages so we don't have id collisions lock (messages) { if (messages.ContainsKey(id)) { //Update the message messages[id].message = value.message; messages[id].to = value.message; } return Get(); } } // DELETE api/<controller>/5 public List<SmsResource> Delete(int id) { if (messages.ContainsKey(id)) { messages.Remove(id); } return Get(); } } Once this class is defined, we should be able to access the WebAPI by a simple GET request using the browser: http://localhost:port/api/SmsResource Notice the commented line: //SentlyPlusSmsSender.SendMessage The SentlyPlusSmsSender class is defined in the attached solution. We have shown this line as commented as we want to explain the core Angular concepts. If you load the attached solution, this line is uncommented in the source and an actual SMS will be sent! By default, the API returns XML. For consumption of the API in Angular, we would like it to return JSON. To change the default to JSON, we make the following change to WebApiConfig.cs file located in the App_Start folder. public static class WebApiConfig { public static void Register(HttpConfiguration config) { config.Routes.MapHttpRoute( name: "DefaultApi", routeTemplate: "api/{controller}/{id}", defaults: new { id = RouteParameter.Optional } ); var appXmlType = config.Formatters.XmlFormatter. SupportedMediaTypes. FirstOrDefault( t => t.MediaType == "application/xml"); config.Formatters.XmlFormatter.SupportedMediaTypes.Remove(appXmlType); } } We now have our backend REST Api which we can consume from Angular! 2. Creating the SmsView.html partial This simple partial will define two fields: the destination phone number (international format starting with a +) and the message. These fields will be bound to model.phoneNumber and model.message. We will also add a button that we shall hook up to sendMessage() in the controller. A list of all previously sent messages (bound to model.allMessages) will also be displayed below the form input. The following code shows the code for the partial: <!--­­ If model.errorMessage is defined, then render the error div -­­> <div class="alert alert-­danger alert-­dismissable" style="margin­-top: 30px;" ng­-show="model.errorMessage != undefined"> <button type="button" class="close" data­dismiss="alert" aria­hidden="true">&times;</button> <strong>Error!</strong> <br /> {{ model.errorMessage }} </div> <!--­­ The input fields bound to the model --­­> <div class="well" style="margin-­top: 30px;"> <table style="width: 100%;"> <tr> <td style="width: 45%; text-­align: center;"> <input type="text" placeholder="Phone number (eg; +44 7778 609466)" ng­-model="model.phoneNumber" class="form-­control" style="width: 90%" onkeypress="return checkPhoneInput();" /> </td> <td style="width: 45%; text-­align: center;"> <input type="text" placeholder="Message" ng­-model="model.message" class="form-­control" style="width: 90%" /> </td> <td style="text-­align: center;"> <button class="btn btn-­danger" ng-­click="sendMessage();" ng-­disabled="model.isAjaxInProgress" style="margin­right: 5px;">Send</button> <img src="/Content/ajax-­loader.gif" ng­-show="model.isAjaxInProgress" /> </td> </tr> </table> </div> <!--­­ The past messages ­­--> <div style="margin-­top: 30px;"> <!­­-- The following div is shown if there are no past messages --­­> <div ng­-show="model.allMessages.length == 0"> No messages have been sent yet! </div> <!--­­ The following div is shown if there are some past messages --­­> <div ng-­show="model.allMessages.length == 0"> <table style="width: 100%;" class="table table-­striped"> <tr> <td>Phone Number</td> <td>Message</td> <td></td> </tr> <!--­­ The ng-­repeat directive is line the repeater control in .NET, but as you can see this partial is pure HTML which is much cleaner --> <tr ng-­repeat="message in model.allMessages"> <td>{{ message.to }}</td> <td>{{ message.message }}</td> <td> <button class="btn btn-­danger" ng-­click="delete(message.smsId);" ng­-disabled="model.isAjaxInProgress">Delete</button> </td> </tr> </table> </div> </div> The above code is commented and should be self explanatory. Conditional rendering is achieved through using the ng-­show=”condition” attribute on various div tags. Input fields are bound to the model and the send button is bound to the sendMessage() function in the controller as through the ng­click=”sendMessage()” attribute defined on the button tag. While AJAX calls are taking place, the controller sets model.isAjaxInProgress to true. Based on this variable, buttons are disabled through the ng-­disabled directive which is added as an attribute to the buttons. The ng-­repeat directive added as an attribute to the tr tag causes the table row to be rendered multiple times much like an ASP.NET repeater. 3. Creating the SmsController controller The penultimate piece of our application is the controller which responds to events from our view and interacts with our MVC4 REST WebAPI. The following listing shows the code we need to add to /app/js/controllers.js. Note that controller definitions can be chained. Also note that this controller “asks for” the $http service. The $http service is a simple way in Angular to do AJAX. So far we have only encountered modules, controllers, views and directives in Angular. The $http is new entity in Angular called a service. More information on Angular services can be found at the following URL: http://docs.angularjs.org/guide/dev_guide.services.understanding_services. .controller('SmsController', ['$scope', '$http', function ($scope, $http) { //We define the model $scope.model = {}; //We define the allMessages array in the model //that will contain all the messages sent so far $scope.model.allMessages = []; //The error if any $scope.model.errorMessage = undefined; //We initially load data so set the isAjaxInProgress = true; $scope.model.isAjaxInProgress = true; //Load all the messages $http({ url: '/api/smsresource', method: "GET" }). success(function (data, status, headers, config) { this callback will be called asynchronously //when the response is available $scope.model.allMessages = data; //We are done with AJAX loading $scope.model.isAjaxInProgress = false; }). error(function (data, status, headers, config) { //called asynchronously if an error occurs //or server returns response with an error status. $scope.model.errorMessage = "Error occurred status:" + status; //We are done with AJAX loading $scope.model.isAjaxInProgress = false; }); $scope.delete = function (id) { //We are making an ajax call so we set this to true $scope.model.isAjaxInProgress = true; $http({ url: '/api/smsresource/' + id, method: "DELETE" }). success(function (data, status, headers, config) { // this callback will be called asynchronously // when the response is available $scope.model.allMessages = data; //We are done with AJAX loading $scope.model.isAjaxInProgress = false; }); error(function (data, status, headers, config) { // called asynchronously if an error occurs // or server returns response with an error status. $scope.model.errorMessage = "Error occurred status:" + status; //We are done with AJAX loading $scope.model.isAjaxInProgress = false; }); } $scope.sendMessage = function () { $scope.model.errorMessage = undefined; var message = ''; if($scope.model.message != undefined) message = $scope.model.message.trim(); if ($scope.model.phoneNumber == undefined || $scope.model.phoneNumber == '' || $scope.model.phoneNumber.length < 10 || $scope.model.phoneNumber[0] != '+') { $scope.model.errorMessage = "You must enter a valid phone number in international format. Eg: +44 7778 609466"; return; } if (message.length == 0) { $scope.model.errorMessage = "You must specify a message!"; return; } //We are making an ajax call so we set this to true $scope.model.isAjaxInProgress = true; $http({ url: '/api/smsresource', method: "POST", data: { to: $scope.model.phoneNumber, message: $scope.model.message } }). success(function (data, status, headers, config) { // this callback will be called asynchronously // when the response is available $scope.model.allMessages = data; //We are done with AJAX loading $scope.model.isAjaxInProgress = false; }). error(function (data, status, headers, config) { // called asynchronously if an error occurs // or server returns response with an error status. $scope.model.errorMessage = "Error occurred status:" + status // We are done with AJAX loading $scope.model.isAjaxInProgress = false; }); } }]); We can see from the previous listing how the functions that are called from the view are defined in the controller. It should also be evident how easy it is to make AJAX calls to consume our MVC4 REST WebAPI. Now we are left with the final piece. We need to define a route that associates a particular path with the view we have defined and the controller we have defined. 4. Add a new route that loads the controller and the partial This is the easiest part of the puzzle. We simply define another route in the /app/js/app.js file: $routeProvider.when('/sms', { templateUrl: '/app/partials/smsview.html', controller: 'SmsController' }); Conclusion In this article we have seen how much of the server side functionality in the MVC4 framework can be moved to the browser thus delivering a snappy and fast user interface. We have seen how we can build client side HTML only views that avoid the messy syntax offered by server side Razor views. We have built a functioning app from the ground up. The significant advantage of this approach to building web apps is that the front end can be completely platform independent. Even though we used ASP.NET to create our REST API, we could just easily have used any other language such as Node.js, Ruby etc without changing a single line of our front end code. Angular is a rich framework and we have only touched on basic functionality required to create a SPA. For readers who wish to delve further into the Angular framework, we would recommend the following URL as a starting point: http://docs.angularjs.org/misc/started. To get started with the code for this project: Sign up for an account at http://plus.sent.ly (free) Add your phone number Go to the “My Identies Page” Note Down your Sender ID, Consumer Key and Consumer Secret Download the code for this article at: https://docs.google.com/file/d/0BzjEWqSE31yoZjZlV0d0R2Y3eW8/edit?usp=sharing Change the values of Sender Id, Consumer Key and Consumer Secret in the web.config file Run the project through Visual Studio!

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