Search Results

Search found 30046 results on 1202 pages for 'linq via c series'.

Page 479/1202 | < Previous Page | 475 476 477 478 479 480 481 482 483 484 485 486  | Next Page >

• Using custom Qt subclasses in Python

  - by kwatford

  First off: I'm new to both Qt and SWIG. Currently reading documentation for both of these, but this is a time consuming task, so I'm looking for some spoilers. It's good to know up-front whether something just won't work. I'm attempting to formulate a modular architecture for some in-house software. The core components are in C++ and exposed via SWIG to Python for experimentation and rapid prototyping of new components. Qt seems like it has some classes I could use to avoid re-inventing the wheel too much here, but I'm concerned about how some of the bits will fit together. Specifically, if I create some C++ classes, I'll need to expose them via SWIG. Some of these classes likely subclass Qt classes or otherwise have Qt stuff exposed in their public interfaces. This seems like it could raise some complications. There are already two interfaces for Qt in Python, PyQt and PySide. Will probably use PySide for licensing reasons. About how painful should I expect it to be to get a SWIG-wrapped custom subclass of a Qt class to play nice with either of these? What complications should I know about upfront?

  Read the article

• Error 5A - Internal CPU Error

  - by Mitch

  So I built myself a pc for the first time. The machine has been running properly, and without issue, since March of this year. Today after an hour or so of gaming the machine shutdown without warning. Any attempts to reboot have been unsuccessful. I have managed to get it to post, twice, but it doesn't get as far as the OS before it shuts off again. I pulled the second video card so I could see the error code LED and it appears to be showing 5A which matches to "Internal CPU Error". Am I looking at a failed CPU or is this a symptom of another issue? Any feedback you can provide is most appreciated. Here's my parts list: CPU: Intel Core i7-4930K 3.4GHz 6-Core CPU Cooler: Corsair H105 73.0 CFM Liquid Motherboard: Asus X79 Deluxe ATX LGA2011 Ram: G.Skill Ripjaws X Series 32GB (4 x 8GB) DDR3-1600 Video card (x2): EVGA GeForce GTX 770 2GB Power supply: Corsair 1000W ATX12V / EPS12V

  Read the article

• Windows Server 2008 scheduled tasks cannot create files

  - by Nick Cartwright

  We have a series of tasks which, when run interactively over the command line run fine creating temporary files and (importantly) logs and backups. When we schedule the task with Administrator privileges to run at the highest priority, however, no logs or temporary files are created! All the directories have read/write privileges as administrator. Has anyone else experienced this?? We are running Windows 2008 Server & the job is configured for 'Windows Vista or Windows Server 2008'. Any help would be much appreciated! OK - so we installed Z-Cron and it works perfectly.... Still a really really strange error from Windows 2008 Task Scheduler, but a solution is perhaps not quite so urgent now we have Z-Cron working!

  Read the article

• Celery / Django Single Tasks being run multiple times

  - by felix001

  I'm facing an issue where I'm placing a task into the queue and it is being run multiple times. From the celery logs I can see that the same worker is running the task ... [2014-06-06 15:12:20,731: INFO/MainProcess] Received task: input.tasks.add_queue [2014-06-06 15:12:20,750: INFO/Worker-2] starting runner.. [2014-06-06 15:12:20,759: INFO/Worker-2] collection started [2014-06-06 15:13:32,828: INFO/Worker-2] collection complete [2014-06-06 15:13:32,836: INFO/Worker-2] generation of steps complete [2014-06-06 15:13:32,836: INFO/Worker-2] update created [2014-06-06 15:13:33,655: INFO/Worker-2] email sent [2014-06-06 15:13:33,656: INFO/Worker-2] update created [2014-06-06 15:13:34,420: INFO/Worker-2] email sent [2014-06-06 15:13:34,421: INFO/Worker-2] FINISH - Success However when I view the actual logs of the application it is showing 5-6 log lines for each step (??). Im using Django 1.6 with RabbitMQ. The method for placing into the queue is via placing a delay on a function. This function (task decorator is added( then calls a class which is run. Has anyone any idea on the best way to troubleshoot this ? Edit : As requested heres the code, views.py In my view im sending my data to the queue via ... from input.tasks import add_queue_project add_queue_project.delay(data) tasks.py from celery.decorators import task @task() def add_queue_project(data): """ run project """ logger = logging_setup(app="project") logger.info("starting project runner..") f = project_runner(data) f.main() class project_runner(): """ main project runner """ def __init__(self,data): self.data = data self.logger = logging_setup(app="project") def self.main(self): .... Code settings.py THIRD_PARTY_APPS = ( 'south', # Database migration helpers: 'crispy_forms', # Form layouts 'rest_framework', 'djcelery', ) import djcelery djcelery.setup_loader() BROKER_HOST = "127.0.0.1" BROKER_PORT = 5672 # default RabbitMQ listening port BROKER_USER = "test" BROKER_PASSWORD = "test" BROKER_VHOST = "test" CELERY_BACKEND = "amqp" # telling Celery to report the results back to RabbitMQ CELERY_RESULT_DBURI = "" CELERY_IMPORTS = ("input.tasks", ) celeryd The line im running is to start celery, python2.7 manage.py celeryd -l info Thanks,

  Read the article

• Is it possible to shuffle a 2D matrix while preserving row AND column frequencies?

  - by j_random_hacker

  Suppose I have a 2D array like the following: GACTG AGATA TCCGA Each array element is taken from a small finite set (in my case, DNA nucleotides -- {A, C, G, T}). I would like to randomly shuffle this array somehow while preserving both row and column nucleotide frequencies. Is this possible? Can it be done efficiently? [EDIT]: By this I mean I want to produce a new matrix where each row has the same number of As, Cs, Gs and Ts as the corresponding row of the original matrix, and where each column has the same number of As, Cs, Gs and Ts as the corresponding column of the original matrix. Permuting the rows or columns of the original matrix will not achieve this in general. (E.g. for the example above, the top row has 2 Gs, and 1 each of A, C and T; if this row was swapped with row 2, the top row in the resulting matrix would have 3 As, 1 G and 1 T.) It's simple enough to preserve just column frequencies by shuffling a column at a time, and likewise for rows. But doing this will in general alter the frequencies of the other kind. My thoughts so far: If it's possible to pick 2 rows and 2 columns so that the 4 elements at the corners of this rectangle have the pattern XY YX for some pair of distinct elements X and Y, then replacing these 4 elements with YX XY will maintain both row and column frequencies. In the example at the top, this can be done for (at least) rows 1 and 2 and columns 2 and 5 (whose corners give the 2x2 matrix AG;GA), and for rows 1 and 3 and columns 1 and 4 (whose corners give GT;TG). Clearly this could be repeated a number of times to produce some level of randomisation. Generalising a bit, any "subrectangle" induced by a subset of rows and a subset of columns, in which the frequencies of all rows are the same and the frequencies of all columns are the same, can have both its rows and columns permuted to produce a valid complete rectangle. (Of these, only those subrectangles in which at least 1 element is changed are actually interesting.) Big questions: Are all valid complete matrices reachable by a series of such "subrectangle rearrangements"? I suspect the answer is yes. Are all valid subrectangle rearrangements decomposable into a series of 2x2 swaps? I suspect the answer is no, but I hope it's yes, since that would seem to make it easier to come up with an efficient algorithm. Can some or all of the valid rearrangements be computed efficiently? This question addresses a special case in which the set of possible elements is {0, 1}. The solutions people have come up with there are similar to what I have come up with myself, and are probably usable, but not ideal as they require an arbitrary amount of backtracking to work correctly. Also I'm concerned that only 2x2 swaps are considered. Finally, I would ideally like a solution that can be proven to select a matrix uniformly at random from the set of all matrices having identical row frequencies and column frequencies to the original. I know, I'm asking for a lot :)

  Read the article

• New Vaio laptop, performing a fresh install

  - by Slace

  I just purchased a new Sony Vaio laptop (z-series) but being a bit of a power user I really want to get rid of the software which is installed on it. I can go through the Programs and Features and manually select each item I want to get rid of, but it's a really tedious process. I'd much prefer to have a clean Windows install which I can then tweak from the get go. But it doesn't appear that I received a Windows 7 install disc (I bought it through a large reseller so it isn't dodgy as far as I know). I do have the Windows 7 licence key on my laptop underside, will this be valid if I use a Windows 7 install disc from work? Or should I have the Windows 7 disk and I need to go back to the reseller?

  Read the article

• Password not accepted when resuming from sleep

  - by Comrade

  My HP Pavilion dv-series notebook will not accept the user account password for the logged in user when resuming from sleep - message returned is Incorrect Password. Simply selecting the Switch User option reloads the login screen and allows me to log in as the same user with the same password that was originally rejected. And, yes I've tried it more than one (hundred) times in case you were thinking it's just a case of slippery fingers. Another interesting point is that it appears to be independent of the software running on the machine. Since the issue first appeared, I have done two clean installs where all HD partitions were wiped and new ones created during fresh installation of the OS. The first such clean install was of Ubuntu (Lucid) 10.04 amd-64, the second of Win 7 Pro 64 (from boxed disc and activated post install). Exactly the same symptoms, described above, are exhibited on both platforms. Have engaged in significant amount of Googling an come up empty so any ideas are welcome.

  Read the article

• What's the best way to work out if a virtual server is overloaded?

  - by zemaj

  I have a series of virtual servers. I'm running a command to login to each one and take a look at the load averages using uptime. What's the best way to work out if load values represent overloading? I'm running on rackspace cloud, so the servers have burst capability and can be all different sizes. I'm a little stumped on how to come up with a consistent way of figuring out when I need to spin up new servers. I can do things like estimate the jobs running on each one, but I'd like a system that runs a little closer to the real resource use available on each instance, as it obviously varies quite a bit! Help greatly appreciated!

  Read the article

• Expose webservice directly to webclients or keep a thin server-side script layer in between?

  - by max

  Hi, I'm developing a REST webservice (Java, Jersey). The people I'm doing this for want to directly access the webservice via Javascript. Some instinct tells me this is not a good idea, but I cannot really explain that instinct. My natural approach would have been to have the webservice do the real logic and database access, but also have some (relatively thin) server-side script layer (e.g. in PHP). Clients would talk to the PHP layer which in turn would talk to the webservice. (The webservice would be pretty local to the apache/PHP server and implicitly trust calls from the script layer. The script layer would take care of session management.) (Btw, I am not talking about just hiding the webservice behind an Apache which simply redirects calls.) But as I find myself at a lack of words/arguments to explain my instinct, I wonder whether my instinct is right - note that while I have been developing all kinds of software in all kinds of languages and frameworks for like 17 years, this is the first time I develop a webservice. So my question is basically: what are your opinions? Are there any standard setups? Is my instinct totally wrong? Or partially? ;P Many thanks, Max PS: I might add a few bits of information about the planned usage of the whole application: will be accessed by different kinds of users, partly general public, partly privileged thus, all major OS/browser combinations can be expected as clients however, writing the client is not my responsibility will potentially have very high load/traffic logic of webservice will later be massively expanded for another product which is basically a superset of the functionality of the current project there is a significant likelihood that at some point an API should be exposed which can be used by 3rd party developers - obviously, with some restrictions at some point, the public view of the product should become accessible via smartphones, too (in other words, maybe a customized version of the site to adapt to the smaller display and different input methods)

  Read the article

• If a cell contains a Symbol, then paste a Description into another cell

  - by Lola

  I'm working on rolling-up a series of charts. I'd like an easy way to summarize by category. The original looks like the sample below but by week for the entire year. I want to know all of the AD 1's, etc. I will need in CA (for each state) by Publication. so the end result would be CA AD 1 PUBLICATION 1 CA AD 2 PUBLICATION 1 CA AD 3 PUBLICATION 1 PUBLICATION 2 PUBLICATION 3 A B C D E 1 PUBLICATION1 CA TX NM AZ 2 AD 1 · 3 AD 2 · · · · 4 AD 3 · · · 5 PUBLICATION2 CA TX NM AZ 6 AD 1 7 AD 2 · · · 8 AD 3 · · · 9 PUBLICATION3 CA TX NM AZ 10 AD 1 11 AD 2 · · · 12 AD 3 · · · Thanks so much!

  Read the article

• Prevent Excel Chart Data Labels overlapping

  - by Nicholas

  I have an Excel dashboard with line charts containing data labels. Specifically, we are only using the data labels at the rightmost end of the lines, and the labels consist of the Series name and final value. By changing a dropdown, the dashboard is automatically updated to give 19 different dashboards. The problem is that we can't work out any way of preventing the labels overlapping. Everything else on the dashboard can be made to automatically update nicely, except for this. Can anybody think of a way to do this? E.g. plugin or macro.

  Read the article

• What are these completely random images that pop up when using Recuva?

  - by Qubert

  I just used Recuva to get back some photos I accidentally deleted on C:, but I also noticed there's a bunch of COMPLETELY random images in the list of recoverable files I can choose from. An example would be, There are images with names like John_Doe.jpg with a file path somewhere out of C:/Windows/Assembly/ And some of these things don't even make sense, there's one called componentsSpriteImage with the path C:/?/Images that shows a "poster" from the TV series Gold Rush. I am completely lost on this.. I know the OS is on C:, but I can't really think of a reason why Microsoft would leave a image hanging around from Gold Rush.

  Read the article

• Problems installing a package from PyPI: root files not installed

  - by intuited

  After installing the BitTorrent-bencode package, either via easy_install BitTorrent-bencode or pip install BitTorrent-bencode, or by downloading the tarball and installing that via easy_install $tarball, I discover that /usr/local/lib/python2.6/dist-packages/BitTorrent_bencode-5.0.8-py2.6.egg/ contains EGG-INFO/ and test/ directories. Although both of these subdirectories contain files, there are no files in the BitTorr* directory itself. The tarball does contain bencode.py, which is meant to be the actual source for this package, but it's not installed by either of those utils. I'm pretty new to all of this so I'm not sure if this is a problem with the package or with what I'm doing. The package was packaged a while ago (2007), so perhaps it's using some deprecated configuration aspect that I need to supply a command-line flag for. I'm more interested in learning what's wrong with either the package or my procedures than in getting this particular package installed; there is another package called hunnyb that seems to do a decent enough job of decoding bencoded data. Mostly I'd like to know how to deal with such problems in other packages.

  Read the article

• Creating 1 page PDF of iPad Screen view - How?

  - by user314695

  Hi All, I've asked this question on a couple other forums and have had zero response, so I'm hoping someone here can help point me in the right direction. I have a pretty simple one screen application for my work. It's basically just a recreation of a 1 page paper report that has a company logo, some labels, a few text boxes and a scroll text box for the report. I need to be able to fill out the report then click a button to save it in a graphical form so I can fax, print or email it later. Currently, I'm just programmatically taking a screen capture and saving it to the photo's library (default for screen capture). Then I can just email it from photo's. This works ok, but is kind of hacky, at best. I've read through the new iPad 3.2 guide for creating PDF's (apparently it's supposed to be much easier than before) but I can not get it to work and I've spent countless hours on it now. I'm hoping someone has the answer for me. Alternatively, if anyone knows how I can redirect where the screen capture is stored (default is in the photo album) then maybe I can make that function work. If I could redirect the screen capture to store in my applications document folder, then I can use MFMailCompose to attach it to an email. Lastly, on a side note, does anyone know of a good way to capture a digital signature via touch. For instance, I'd love to have my users be able to just sign their name via touch at the bottom of the document before I convert to PDF or take a screen capture. Thanks in advance for your help. -Ray

  Read the article

• Will installing an Ultra ATA cable backwards affect performance?

  - by GMMan

  I've recently purchased a hard drive upgrade for my Xbox 320GB WD Caviar Blue WD3200AAJB and StarTech.com Ultra ATA/66/100/133 cable IDE66 yes I'm crazy When it came to installing the cable, it was too short (my fault), and there wasn't enough space between the master and slave ends to reach both the DVD drive and the hard drive. The only thing I could do was install the cable backwards and twisting it quite a bit to make it fit. The upgrade works, but reading the manual for the hard drive I replaced (10GB Seagate U Series 5), apparently there is a specific way you have to connect the cable. I don't have that option, so the question comes down to, will my drive performance be at Ultra ATA levels, or is it still performing at original ATA speeds? Is there any way I can test this (benchmarking software for Xbox)?

  Read the article

• FTP exception 501 "pathname" more than 8 characters

  - by BigMac66

  I am trying to access a file via a URI using the FTP protocol. For obvious security reasons I had to make some changes but this is where the problems seem to be coming from. My URI is as follows: ftp://user:[email protected]/u/Bigpathname/XYZ/ABC/BigPathname/bigpathname/xyz/abc/MY_LOG.LOG And I see this exception: sun.net.ftp.FtpProtocolException: CWD Bigpathname:501 A qualifier in "Bigpathname" is more than 8 characters This is really confusing as I can access the file from a Windows 7 command line with the CD command just fine. Both one directory at a time and as a full path. I found one article mentioning that MVS file names must be 8 or fewer characters but this does not explain how I can get to these same files from my command line! They do exist there is data there that I can download manual but I can not get there via a URI in Java. PS I use .toURL().openStream() to get files on my local machine just fine, it only fails when I try to get them from my server. EDIT October 1st I am able to access files on the MVS host using FileZilla and the basic FTP client from the Windows 7 command line - but I still cannot get them from a URI/URL. I downloaded a very basic Java built FTP client and tried accessing the same file in my program from there and the path works but because my file name has a dot in it "MY_LOG.LOG" I am getting File does not exist 501 Invalid data set name "MY_LOG.LOG". Use MVS Dsname conventions. I am utterly perplexed by this...

  Read the article

• multiple form submission with one submit

  - by skylab

  I've been trying to think this through and figure out if it is possible or not. I'm using zen-cart as shopping cart software, but what I'd like to do, is hard code a page that is basically a list of 7-9 products, next to each product is a checkbox, so I'd like to figure out a way, via html,javascript or jquery to submit whichever forms(products) are checked to the cart. The typical form submission for a product looks something like this(sometimes there may be one or two additional hidden fields): <form name="cart_quantity" action="index.php?action=add_product" method="post" enctype="multipart/form-data"> <input type="hidden" name="cart_quantity" value="1"> <input type="hidden" name="products_id" value="7"> <input type="hidden" name="id[6]" value="9" id="attrib-6-9"> <input type="image" src="buy_button.png" alt="Add to Cart" title="Instructional Video Part 1: Add to Cart"> </form> There would be 7-9 of these on the page, each with a checkbox, so I'm assuming a script would need to figure out which ones where checked and submit them via the form action? Maybe there is a better way of going about this that I'm not thinking of because a)it's over my head or b)just haven't figured it out yet. Anyway is something like this possible?

  Read the article

• Organizing development teams

  - by Patrick

  A long time ago, when my company was much smaller, dividing the development work over teams was quite easy: the 'application' team developed the applications-specific logic, often requiring a deep insight of specific industry problems) the 'generic' team developed the parts that were common/generic for all applications (user interface related stuff, database access, low-level Windows stuff, ...) Over the years the boundaries between the teams have become fuzzy: the 'application' teams often write application-specific functionality with a 'generic' part, so instead of asking the 'generic' team to write that part for them, they write it themselves to speed up the developments; then donate it to the 'generic' team the 'generic' team's focus seems to be more 'maintenance oriented'. All of the 'very generic' code has already been written, so no new developments are needed in it, but instead they continuously have to support all the functionality donated by the application teams. All this seems to indicate that it's not a good idea anymore to have this split in teams. Maybe the 'generic' team should evolve into a 'software quality' team (defining and guarding the rules for writing good quality software), or into a 'software deployment' team (defining how software should be deployed, installed, ...). How do you split up the work in different teams if you have different applications? everybody can write generic code and donates it to a central 'generic' team? everybody can write generic code, but nobody 'manages' this generic code (everybody is the owner) generic code is written by a 'generic' team only and the applications have to wait until the 'generic' team delivers the generic part (via a library, via a DLL) there is no overlap in code between the different applications some other way? Notice that thee advantage of having the mix (allowing everybody to write everywhere in the code) is that: code is written in a more flexible way it's easier to debug the code since you can easily step into the 'generic' code in the debugger But the big (and maybe only) disadvantage is that this generic code may become nobody's responsibility if there is no clear team that manages it anymore. What is your vision?

  Read the article

• Open Source Outlook and Exchange Alternative (for Calendar and Tasks)

  - by Elmar Weber

  We're using an Exchange Server and Outlook in a private context. Since Exchange is getting more and more of a monster to maintain and is basically the only thing running on a Windows VM Server, I'm looking for an alternative with the following properties: Server based back-end that that can be installed / deployed on my machine and is not dependent on any third party services (e.g. Google Calendar). (Easy) import of existing Outlook calendars, either via some feature of Exchange or by ex- and importing from Outlook. Roughly the basic features of the Outlook calendar (categorizations, series, etc) Synchronization with the iPhone over wireless without a hitch (e.g. double or missing entries) Any recommendations?

  Read the article

• Boot Linux from DOS (with loadlin.exe etc)

  - by dreamlax

  I have been using the latest version of loadlin.exe (version 1.6e). It works on some machines but on others I get "no place after kernel for initrd". The kernel is about 5MB in size (non-modular) and my initrd image (decompressed) is about 8MB. One route that I could take is to enable module support and offload some of the weight of the kernel into the initrd image but I'm not confident this will rectify the issue. Are there any alternatives to loadlin.exe that are capable of loading Linux from a booted DOS session? I basically have a series of DOS tools that I'd like to run one after another and then boot into Linux, which loadlin.exe seems to be working very well for except on some machines.

  Read the article

• Switch to switch encryption over a wireless bridge (TrustSec?)

  - by metatheorem

  I am planning to connect an existing Cisco 3750 switch to a 3560C switch over a wireless PTP bridge. The bridge will be WPA2 protected, but I am looking for an additional measure of security between the switches to prevent other wireless access through either switch. They do not support IPSec, only 802.1Q tunnels, and buying additional hardware is not likely an option. I am looking into using TrustSec manual mode between the switches. After some effort reading into TrustSec and MACsec, I am mostly certain this is a good choice over the wireless bridge, keeping in mind it is a shared medium. Two questions: Can I reliably prevent other wireless traffic from accessing the switches using TrustSec? Does anyone know of any better options with the 3000 series switches?

  Read the article

• Does a modern PC require a graphics card to run?

  - by ArtM

  As I can remember, on old systems (Pentium II or III) it was not possible to boot and run the PC if the graphics card was missing (AGP cards were used in those days). Many years from then, I'm using motherboards with integrated graphics and I have no experience related to this subject, the "graphics card" always was present. Currently I intend to build a home/private "server" for my purposes and most of the motherboards I want to buy have no integrated graphics (AMD 870 or 970). I can take a normal graphics card from my firends for a few hours/days and use it when installing the necessary software. The question is: can I boot and run the PC without problems after I install everything I need and the graphics card is removed? if a general answer cannot be given, at least some examples of manufacturers/MB series/MB models will be helpfull I think it's obvious, but for completeness: I mean cheap desktop components, not real servers.

  Read the article

• zune - how do i make the PC zune download a movie, not stream it?

  - by bharal

  As the title suggests - I have bought a tv show series season on PC Zune. My gf watched the show, and now i'd like to be able to watch the show too. The catch - i'm going to go overseas on a trip soon, and i'd like to be able to watch the show from outside the US. Given that Zune won't let me stream things overseas (past experience, anyway), I would like to download the show to my computer and watch it that way. The problem is that although the full season has been "watched" it appears it was only streamed, not downloaded. Or rather, that one episode was downloaded, and the rest streamed. I bought a season pass (so all the episodes at once) and the show was bought, not rented. How do i make Zune download, not stream, a show?

  Read the article

• How can I filter then modify e-mails using IMAP?

  - by swolff1978

  I have asked this question in a different post here on SO: How can a read receipt be suppressed? I have been doing some research of my own to try and solve this problem and accessing the e-mail account via IMAP seems like it is going to be a good solution. I have successfully been able to access my own Inbox and mark messages as read with no issue. I have been asked to preform the same task on an Inbox that contains over 23,000 emails. I would like to run the test on a small amount of e-mails from that inbox before letting the whole 23,000 get it. Here is the code I have been running via telnet: . LOGIN [email protected] password . SELECT Inbox . STORE 1:* flags \Seen 'this line marks all the e-mails as read So my question is how can i execute that store command on a specific group of e-mails... say emails that are going to / coming from a specific account? Is there a way to like concatenate the commands? like a FETCH then the STORE? Or is there a better way to go about getting a collection of e-mails based on certain criteria and then modifying ONLY those e-mails that can be accomplished through IMAP?

  Read the article

• Ways to make (relatively) safe assumptions about the type of concrete subclasses?

  - by Kylotan

  I have an interface (defined as a abstract base class) that looks like this: class AbstractInterface { public: bool IsRelatedTo(const AbstractInterface& other) const = 0; } And I have an implementation of this (constructors etc omitted): class ConcreteThing { public: bool IsRelatedTo(const AbstractInterface& other) const { return m_ImplObject.has_relationship_to(other.m_ImplObject); } private: ImplementationObject m_ImplObject; } The AbstractInterface forms an interface in Project A, and the ConcreteThing lives in Project B as an implementation of that interface. This is so that code in Project A can access data from Project B without having a direct dependency on it - Project B just has to implement the correct interface. Obviously the line in the body of the IsRelatedTo function cannot compile - that instance of ConcreteThing has an m_ImplObject member, but it can't assume that all AbstractInterfaces do, including the other argument. In my system, I can actually assume that all implementations of AbstractInterface are instances of ConcreteThing (or subclasses thereof), but I'd prefer not to be casting the object to the concrete type in order to get at the private member, or encoding that assumption in a way that will crash without a diagnostic later if this assumption ceases to hold true. I cannot modify ImplementationObject, but I can modify AbstractInterface and ConcreteThing. I also cannot use the standard RTTI mechanism for checking a type prior to casting, or use dynamic_cast for a similar purpose. I have a feeling that I might be able to overload IsRelatedTo with a ConcreteThing argument, but I'm not sure how to call it via the base IsRelatedTo(AbstractInterface) method. It wouldn't get called automatically as it's not a strict reimplementation of that method. Is there a pattern for doing what I want here, allowing me to implement the IsRelatedTo function via ImplementationObject::has_relationship_to(ImplementationObject), without risky casts? (Also, I couldn't think of a good question title - please change it if you have a better one.)

  Read the article

< Previous Page | 475 476 477 478 479 480 481 482 483 484 485 486  | Next Page >