Search Results

Search found 9934 results on 398 pages for 'lambda functions'.

Page 23/398 | < Previous Page | 19 20 21 22 23 24 25 26 27 28 29 30  | Next Page >

• binding media keys to functions in vlc player

  - by Eknath Iyer

  How do I bind the media keys (play pause stop forward .. ) to corresponding functions in the vlc player. For now, I have to use the spacebar for play/pause and stuff like that. I'd prefer being able to vlc even when it is minimized!

  Read the article

• How to automatically define functions and aliases on remote server after ssh login

  - by Ramon

  I want to define bash functions and aliases in my remote shell automatically on login. I can't put the definitions into .profile or similar because the users I log in as are often shared with others who use the same systems and I don't have control of this. What I'm trying to do is execute a few bash function definitions in the remote process and then continue as a login shell. I tried this but it did not work: cat ~/.profile - | ssh -tt user@host bash -l Any ideas?

  Read the article

• VBA + Polymorphism: Override worksheet functions from 3rd party

  - by phi

  my company makes extensive use of a data provider using a (closed source) VBA plugin. In principal, every query follows follows a certain structure: Fill one cell with a formula, where arguments to the formula specify the query the range of that formula is extended (not an arrray formula!) and cells below/right are filled with data For this to work, however, a user has to have a terminal program installed on the machine, as well as a com-plugin referenced in VBA/Excel. My Problem These Excelsheets are used and extended by multiple users, and not all of them have access to the data provider. While they can open the sheet, it will recalculate and the data will be gone. However, frequent recalculation is required. I would like every user to be able to use the sheets, without executing a very specific set of formulas. Attempts remove the reference on those computers where I do not have terminal access. This generates a NAME error i the cell containing the query (acceptable), but this query overrides parts of the data (not acceptable) If you allow the program to refresh, all data will be gone after a failed query Replace all formulas with the plain-text result in the respective cells (press a button and loop over every cell...). Obviously destroys any refresh-capabilities the querys offer for all subsequent users, so pretty bad, too. A theoretical idea, and I'm not sure how to implement it: Replace the functions offered by the plugin with something that will be called either first (and relay the query through to the original function, if thats available) or instead of the original function (by only deploying the solution on non-terminal machines), which just returns the original value. More specifically, if my query function is used like this: =GETALLDATA(Startdate, Enddate, Stockticker, etc) I would like to transparently swap the function behind the call. Do you see any hope, or am I lost? I appreciate your help. PS: Of course I'm talking about Bloomberg... Some additional points to clarify issues raise by Frank: The formula in the sheets may not be changed. This is mission-critical software, and its way too complex for any sane person to try and touch it. Only excel and VBA may be used (which is the reason for the previous point...) It would be sufficient to prevent execution of these few specific formulas/functions on a specific machine for all excel sheets to come This looks more and more like a problem for stackoverflow ;-)

  Read the article

• When is LINQ (to objects) Overused?

  - by Mystagogue

  My career started as a hard-core functional-paradigm developer (LISP), and now I'm a hard-care .net/C# developer. Of course I'm enamored with LINQ. However, I also believe in (1) using the right tool for the job and (2) preserving the KISS principle: of the 60+ engineers I work with, perhaps only 20% have hours of LINQ / functional paradigm experience, and 5% have 6 to 12 months of such experience. In short, I feel compelled to stay away from LINQ unless I'm hampered in achieving a goal without it (wherein replacing 3 lines of O-O code with one line of LINQ is not a "goal"). But now one of the engineers, having 12 months LINQ / functional-paradigm experience, is using LINQ to objects, or at least lambda expressions anyway, in every conceivable location in production code. My various appeals to the KISS principle have not yielded any results. Therefore... What published studies can I next appeal to? What "coding standard" guideline have others concocted with some success? Are there published LINQ performance issues I could point out? In short, I'm trying to achieve my first goal - KISS - by indirect persuasion. Of course this problem could be extended to countless other areas (such as overuse of extension methods). Perhaps there is an "uber" guide, highly regarded (e.g. published studies, etc), that takes a broader swing at this. Anything?

  Read the article

• C++: Explicit DLL Loading: First-chance Exception on non "extern C" functions

  - by Shiftbit

  I am having trouble importing my C++ functions. If I declare them as C functions I can successfully import them. When explicit loading, if any of the functions are missing the extern as C decoration I get a the following exception: First-chance exception at 0x00000000 in cpp.exe: 0xC0000005: Access violation. DLL.h: extern "C" __declspec(dllimport) int addC(int a, int b); __declspec(dllimport) int addCpp(int a, int b); DLL.cpp: #include "DLL.h" int addC(int a, int b) { return a + b; } int addCpp(int a, int b) { return a + b; } main.cpp: #include "..DLL/DLL.h" #include <stdio.h> #include <windows.h> int main() { int a = 2; int b = 1; typedef int (*PFNaddC)(int,int); typedef int (*PFNaddCpp)(int,int); HMODULE hDLL = LoadLibrary(TEXT("../Debug/DLL.dll")); if (hDLL != NULL) { PFNaddC pfnAddC = (PFNaddC)GetProcAddress(hDLL, "addC"); PFNaddCpp pfnAddCpp = (PFNaddCpp)GetProcAddress(hDLL, "addCpp"); printf("a=%d, b=%d\n", a,b); printf("pfnAddC: %d\n", pfnAddC(a,b)); printf("pfnAddCpp: %d\n", pfnAddCpp(a,b)); //EXCEPTION ON THIS LINE } getchar(); return 0; } How can I import c++ functions for dynamic loading? I have found that the following code works with implicit loading by referencing the *.lib, but I would like to learn about dynamic loading. Thank you to all in advance.

  Read the article

• Lambdas within Extension methods: Possible memory leak?

  - by Oliver

  I just gave an answer to a quite simple question by using an extension method. But after writing it down i remembered that you can't unsubscribe a lambda from an event handler. So far no big problem. But how does all this behave within an extension method?? Below is my code snipped again. So can anyone enlighten me, if this will lead to myriads of timers hanging around in memory if you call this extension method multiple times? I would say no, cause the scope of the timer is limited within this function. So after leaving it no one else has a reference to this object. I'm just a little unsure, cause we're here within a static function in a static class. public static class LabelExtensions { public static Label BlinkText(this Label label, int duration) { Timer timer = new Timer(); timer.Interval = duration; timer.Tick += (sender, e) => { timer.Stop(); label.Font = new Font(label.Font, label.Font.Style ^ FontStyle.Bold); }; label.Font = new Font(label.Font, label.Font.Style | FontStyle.Bold); timer.Start(); return label; } }

  Read the article

• How can you assign multiple Javascript functions to the upload_start_handler for WordPress's SWFUplo

  - by Byron

  I've got 2 WordPress plugins (PhotoSmash and TwitPic-It) that need to hook into the SWFUploader for the Media Uploader in WordPress. SWFUpload has a setting "upload_start_handler" where you can specify a javascript function that will run immediately before the upload begins. The trouble is that I need to assign 2 different functions to run in separate plugins that may or may not coexist in a given user's WordPress blog. I want to make the implementation so that it allows other plugin authors to hook their own javascript functions. I don't know that I have access to the actual event being fired. The "upload_start_handler" is a setting on a JS object, not an event hook on the flash object. You set it like: swfu.settings.upload_start_handler = function(){ runFlashStartUploadFunctions(); } My current plan is to add a 2 functions and an array variable (check if they exists first). The array variable is intended to hold an array of function names (strings) to run when "runFlashStartUploadFunctions" gets called at upload start. The first function is to add new functions to the array. The second function is "runFlashStartUploadFunctions", and it will iterate through the array and eval each function name. Is there a better way? Thanks, Byron

  Read the article

• Delegate within a delegate in VB.NET.

  - by Topdown

  I am trying to write a VB.NET alternative to a C# anonymous function. I wish to call Threading.SynchronizationContext.Current.Send which expects a delegate of type Threading.SendOrPostCallback to be passed to it. The background is here, but because I wish to both pass in a string to MessageBox.Show and also capture the DialogResult I need to define another delegate within. I am struggling with the VB.NET syntax, both from the traditional delegate style, and lambda functions. My go at the traditional syntax is below, but I have gut feeling it should be much simpler than this: Private Sub CollectMesssageBoxResultFromUserAsDelegate(ByVal messageToShow As String, ByRef wasCanceled As Boolean) wasCanceled = False If Windows.Forms.MessageBox.Show(String.Format("{0}{1}Please press [OK] to ignore this error and continue, or [Cancel] to stop here.", messageToShow), "Continue", Windows.Forms.MessageBoxButtons.OKCancel, Windows.Forms.MessageBoxIcon.Exclamation) = Windows.Forms.DialogResult.Cancel Then wasCanceled = True End If End Sub Private Delegate Sub ShowMessageBox(ByVal messageToShow As String, ByRef canceled As Boolean) Private Sub AskUserWhetherToCancel(ByVal message As String, ByVal args As CancelEventArgs) If args Is Nothing Then args = New System.ComponentModel.CancelEventArgs With {.Cancel = False} Dim wasCancelClicked As Boolean Dim firstDelegate As New ShowMessageBox(AddressOf CollectMesssageBoxResultFromUserAsDelegate) '…. Now what?? 'I can’t declare SendOrPostCallback as below: 'Dim myDelegate As New Threading.SendOrPostCallback(AddressOf firstDelegate) End Sub

  Read the article

• Calling Model Functions from a Library

  - by Abs

  Hello all, I have turned a normal PHP class into a library so I can use it in Codeigniter as a library. I can load it and call the functions I need in that class. Here is that class to help with the question. However, there are quite a few points where I have to call functions in my class. These functions reside in the model that instantiated my class. How can I do this as currently normal calls don't work. Here is my code: class Controlpanel_model extends Model { var $category = ''; var $dataa = 'a'; function Controlpanel_model(){ parent::Model(); } function import_browser_bookmarks(){ $this->load->library('BookmarkParser'); /* *In this function call to the class I pass * what model functions exist that it should call * You can view how this done by clicking the link above and looking at line 383 */ $this->bookmarkparser->parseNetscape("./bookmarks.html", 0, 'myURL', 'myFolder'); return $this->dataa; } function myURL($data, $depth, $no) { $category = $this->category; $this->dataa .= 'Tag = '.$category.'<br />'.'URL = '.$data["url"].'<br />'.'Title = '.$data["descr"].'<br />'.'<br /><br />'; } function myFolder($data, $depth, $no) { $this->category = $data["name"]; } } Thanks all for any help.

  Read the article

• linq-to-sql combine child expressions

  - by VictorS

  I need to create and combine several expressions for child entity into one to use it on "Any" operator of a parent. Code now looks like this: Expresion<Child, bool> startDateExpression = t => t.start_date >= startDate; Expression<Child, bool> endDateExpression = t => t.end_date <= endDate; .... ParameterExpression param = startDateExpression.Parameters[0]; Expression<Func<T, bool>> Combined = Expression.Lambda<Func<Child, bool>>( Expression.AndAlso(startDateExpression.Body, startDateExpression.Body), param); //but now I am trying to use combined expression on parent //this line fails just to give an idea on what I am trying to do: //filter type is IQueryable<Parent>; var filter = filter.Where(p =>p.Children.Any(Combined)); How can I do that? Is there better(more elegant way way of doing it?

  Read the article

• How can I get this dynamic WHERE statement in my LINQ-to-XML to work?

  - by Edward Tanguay

  In this question Jon Skeet offered a very interesting solution to making a LINQ-to-XML statement dynamic, but my knowledge of lambdas and delegates is not yet advanced enough to implement it: I've got it this far, but of course I get the error "smartForm does not exist in the current context": private void LoadWithId(int id) { XDocument xmlDoc = null; try { xmlDoc = XDocument.Load(FullXmlDataStorePathAndFileName); } catch (Exception ex) { throw new Exception(String.Format("Cannot load XML file: {0}", ex.Message)); } Func<XElement, bool> whereClause = (int)smartForm.Element("id") == id"; var smartForms = xmlDoc.Descendants("smartForm") .Where(whereClause) .Select(smartForm => new SmartForm { Id = (int)smartForm.Element("id"), WhenCreated = (DateTime)smartForm.Element("whenCreated"), ItemOwner = smartForm.Element("itemOwner").Value, PublishStatus = smartForm.Element("publishStatus").Value, CorrectionOfId = (int)smartForm.Element("correctionOfId"), IdCode = smartForm.Element("idCode").Value, Title = smartForm.Element("title").Value, Description = smartForm.Element("description").Value, LabelWidth = (int)smartForm.Element("labelWidth") }); foreach (SmartForm smartForm in smartForms) { _collection.Add(smartForm); } } Ideally I want to be able to just say: var smartForms = GetSmartForms(smartForm=> (int) smartForm.Element("DisplayOrder").Value > 50); I've got it this far, but I'm just not grokking the lambda magic, how do I do this? public List<SmartForm> GetSmartForms(XDocument xmlDoc, XElement whereClause) { var smartForms = xmlDoc.Descendants("smartForm") .Where(whereClause) .Select(smartForm => new SmartForm { Id = (int)smartForm.Element("id"), WhenCreated = (DateTime)smartForm.Element("whenCreated"), ItemOwner = smartForm.Element("itemOwner").Value, PublishStatus = smartForm.Element("publishStatus").Value, CorrectionOfId = (int)smartForm.Element("correctionOfId"), IdCode = smartForm.Element("idCode").Value, Title = smartForm.Element("title").Value, Description = smartForm.Element("description").Value, LabelWidth = (int)smartForm.Element("labelWidth") }); }

  Read the article

• List<object>.RemoveAll - How to create an appropriate Predicate

  - by CJM

  This is a bit of noob question - I'm still fairly new to C# and generics and completely new to predicates, delegates and lamda expressions... I have a class 'Enquiries' which contains a generic list of another class called 'Vehicles'. I'm building up the code to add/edit/delete Vehicles from the parent Enquiry. And at the moment, I'm specifically looking at deletions. From what I've read so far, it appears that I can use Vehicles.RemoveAll() to delete an item with a particular VehicleID or all items with a particular EnquiryID. My problem is understanding how to feed .RemoveAll the right predicate - the examples I have seen are too simplistic (or perhaps I am too simplistic given my lack of knowledge of predicates, delegates and lambda expressions). So if I had a List<Of Vehicle> Vehicles where each Vehicle had an EnquiryID, how would I use Vehicles.RemoveAll() to remove all vehicles for a given EnquiryID? I understand there are several approaches to this so I'd be keen to hear the differences between approaches - as much as I need to get something working, this is also a learning exercise. As an supplementary question, is a Generic list the best repository for these objects? My first inclination was towards a Collection, but it appears I am out of date. Certainly Generics seem to be preferred, but I'm curious as to other alternatives. Thanks

  Read the article

• topic-comment naming of functions/methods

  - by Daniel

  I was looking at American Sign Language the other day... and I noticed that the construction of the language was topic-comment. As in "Weather is good". That got me to thinking about why we name methods/functions in the manner of: function getName() { ... } function setName(v) { ... } If we think about naming in a topic-comment function, the function names would be function nameGet() { ... } function nameSet() { ... } This might be better for a class had multiple purposes. IE: class events { function ListAdd(); function ListDelete(); function ListGet(); function EventAdd(); function EventDelete(); function EventGet(); } This way the functions are grouped by "topic". Where as the former naming, functions are grouped Action-Noun, but are sorted by Noun. I thought this was an interesting POV, what do other people think about naming functions/methods Topic-Comment? Obviously, mixing naming conventions up in the same project would be weird, but overall? -daniel

  Read the article

• PHP: passing a function with parameters as parameter

  - by Oden

  Hey, I'm not sure that silly question, but I ask: So, if there is an anonymous function I can give it as another anonymous functions parameter, if it has been already stored a variable. But, whats in that case, if I have stored only one function in a variable, and add the second directly as a parameter into it? Can I add parameters to the non-stored function? Fist example (thats what i understand :) ): $func = function($str){ return $str; }; $func2 = function($str){ return $str; }; $var = $func($func2('asd')); var_dump($var); // prints out string(3) "asd" That makes sense for me, but what is with the following one? $func = function($str){ return $str; }; $var = $func(function($str = "asd"){ return $str; }); var_dump($var); /** This prints out: object(Closure)#1 (1) { ["parameter"]=> array(1) { ["$str"]=> string(10) "" } } But why? */ And at the end, can someone recommend me a book or an article, from what i can learn this lambda coding feature of php? Thank you in advance for your answers :)

  Read the article

• Are function-local typedefs visible inside C++0x lambdas?

  - by GMan - Save the Unicorns

  I've run into a strange problem. The following simplified code reproduces the problem in MSVC 2010 Beta 2: template <typename T> struct dummy { static T foo(void) { return T(); } }; int main(void) { typedef dummy<bool> dummy_type; auto x = [](void){ bool b = dummy_type::foo(); }; // auto x = [](void){ bool b = dummy<bool>::foo(); }; // works } The typedef I created locally in the function doesn't seem to be visible in the lambda. If I replace the typedef with the actual type, it works as expected. Here are some other test cases: // crashes the compiler, credit to Tarydon int main(void) { struct dummy {}; auto x = [](void){ dummy d; }; } // works as expected int main(void) { typedef int integer; auto x = [](void){ integer i = 0; }; } I don't have g++ 4.5 available to test it, right now. Is this some strange rule in C++0x, or just a bug in the compiler? From the results above, I'm leaning towards bug. Though the crash is definitely a bug. For now, I have filed two bug reports. All code snippets above should compile. The error has to do with using the scope resolution on locally defined scopes. (Spotted by dvide.) And the crash bug has to do with... who knows. :) Update According to the bug reports, they have both been fixed for the next release of Visual Studio 2010.

  Read the article

• What OpenGL functions are not GPU accelerated?

  - by Xavier Ho

  I was shocked when I read this (from the OpenGL wiki): glTranslate, glRotate, glScale Are these hardware accelerated? No, there are no known GPUs that execute this. The driver computes the matrix on the CPU and uploads it to the GPU. All the other matrix operations are done on the CPU as well : glPushMatrix, glPopMatrix, glLoadIdentity, glFrustum, glOrtho. This is the reason why these functions are considered deprecated in GL 3.0. You should have your own math library, build your own matrix, upload your matrix to the shader. For a very, very long time I thought most of the OpenGL functions use the GPU to do computation. I'm not sure if this is a common misconception, but after a while of thinking, this makes sense. Old OpenGL functions (2.x and older) are really not suitable for real-world applications, due to too many state switches. This makes me realise that, possibly, many OpenGL functions do not use the GPU at all. So, the question is: Which OpenGL function calls don't use the GPU? I believe knowing the answer to the above question would help me become a better programmer with OpenGL. Please do share some of your insights.

  Read the article

• WPF DataGrid populating blank rows on TreeView's SelectedItemChanged

  - by jes9582

  When my DataGrid populates on the TreeView's SelectedItemChanged event it finds the objects and creates the rows accordingly but the rows populate with no text or are just blank. So I know it is finding my objects but it is not displaying them properly. Does anyone see where I made an error or suggest any changes or fixes? Thank you in advance! Here is the CSharp code that is setting the DataGrid's ItemsSource (I am using .dbml and LINQ with Lambda expressions): dgSystemSettings.ItemsSource = (tvSystemConfiguration.SelectedItem as SYSTEM_SETTINGS_GROUP).SYSTEM_SETTINGS_NAMEs.Join(ssdc.SYSTEM_SETTINGS_VALUEs, x => x.SSN_ID, y => y.SSV_SSN_ID, (x, y) => new { SYSTEM_SETTINGS_NAME = x, SYSTEM_SETTINGS_VALUE = y }); And here is the .xaml: <DataGrid Name="dgSystemSettings" AutoGenerateColumns="False" Height="447" Width="513" DockPanel.Dock="Right" ItemsSource="{Binding}" VerticalAlignment="Top" Margin="10,10,0,0"> <DataGrid.Columns> <DataGridTextColumn x:Name="colDisplayName" Header="Name" Binding="{Binding SSN_DISPLAY_NAME}"></DataGridTextColumn> <DataGridTextColumn x:Name="colValue" Header="Value" Binding="{Binding SSV_VALUE}"></DataGridTextColumn> </DataGrid.Columns> </DataGrid>

  Read the article

• How to hide helper functions from public API in c

  - by emge

  I'm working on a project and I need to create an API. I am using sockets to communicate between the server (my application) and the clients (the other applications using my API). This project is in c not C++ I come from a linux background and this is my first project using Windows, Visual Studio 2008, and dll libraries. I have communication working between the client and server, but I have some that is duplicated on both projects. I would like to create a library (probably a dll file), that both projects can link to so I don't have to maintain extra code. I also have to create the library that has the API that I need to make available for my clients. Within the API functions that I want public are the calls to these helper functions that are "duplicated code", I don't want to expose these functions to my client, but I do want my server to be able to use those functions. How can I do this? I will try to clarify with an example. This is what I started with. Server Project: int Server_GetPacket(SOCKET sd); int ReceiveAll(SOCKET sd, char *buf, int len); int VerifyLen(char *buf); Client Project: int Client_SendCommand(int command); int Client_GetData(int command, char *buf, int len); int ReceiveAll(SOCKET sd, char *buf, int len); int VerifyLen(char *buf); This is kind of what I would like to end up with: //Server Project: int Server_GetPacket(SOCKET sd); // library with public and private types // private API (not exposed to my client) int ReceiveAll(SOCKET sd, char *buf, int len); int VerifyLen(char *buf); // public API (header file available for client) int Client_SendCommand(int command); int Client_GetData(int command, char *buf, int len); Thanks any help would be appreciated.

  Read the article

• Which OpenGL functions are not GPU-accelerated?

  - by Xavier Ho

  I was shocked when I read this (from the OpenGL wiki): glTranslate, glRotate, glScale Are these hardware accelerated? No, there are no known GPUs that execute this. The driver computes the matrix on the CPU and uploads it to the GPU. All the other matrix operations are done on the CPU as well : glPushMatrix, glPopMatrix, glLoadIdentity, glFrustum, glOrtho. This is the reason why these functions are considered deprecated in GL 3.0. You should have your own math library, build your own matrix, upload your matrix to the shader. For a very, very long time I thought most of the OpenGL functions use the GPU to do computation. I'm not sure if this is a common misconception, but after a while of thinking, this makes sense. Old OpenGL functions (2.x and older) are really not suitable for real-world applications, due to too many state switches. This makes me realise that, possibly, many OpenGL functions do not use the GPU at all. So, the question is: Which OpenGL function calls don't use the GPU? I believe knowing the answer to the above question would help me become a better programmer with OpenGL. Please do share some of your insights.

  Read the article

• [C++] Trouble declaring and recognizing global functions

  - by Sarah

  I've created some mathematical functions that will be used in main() and by member functions in multiple host classes. I was thinking it would be easiest to make these math functions global in scope, but I'm not sure how to do this. I've currently put all the functions in a file called Rdraws.cpp, with the prototypes in Rdraws.h. Even with all the #includes and externs, I'm getting a "symbol not found" error at the first function call in main(). Here's what I have: // Rdraws.cpp #include <cstdlib> using namespace std; #include <cmath> #include "Rdraws.h" #include "rng.h" extern RNG rgen // this is the PRNG used in the simulation; global scope void rmultinom( double p_trans[], int numTrials, int numTrans, int numEachTrans[] ) { // function 1 def } void rmultinom( const double p_trans[], const int numTrials, int numTrans, int numEachTrans[]) { // function 2 def } int rbinom( int nTrials, double pLeaving ) { // function 3 def } // Rdraws.h #ifndef RDRAWS #define RDRAWS void rmultinom( double[], int, int, int[] ); void rmultinom( const double[], const int, int, int[] ); int rbinom( int, double ); #endif // main.cpp ... #include "Rdraws.h" ... extern void rmultinom(double p_trans[], int numTrials, int numTrans, int numEachTrans[]); extern void rmultinom(const double p_trans[], const int numTrials, int numTrans, int numEachTrans[]); extern int rbinom( int n, double p ); ... int main() { ... } I'm pretty new to programming. If there's a dramatically smarter way to do this, I'd love to know.

  Read the article

• Performance difference between functions and pattern matching in Mathematica

  - by Samsdram

  So Mathematica is different from other dialects of lisp because it blurs the lines between functions and macros. In Mathematica if a user wanted to write a mathematical function they would likely use pattern matching like f[x_]:= x*x instead of f=Function[{x},x*x] though both would return the same result when called with f[x]. My understanding is that the first approach is something equivalent to a lisp macro and in my experience is favored because of the more concise syntax. So I have two questions, is there a performance difference between executing functions versus the pattern matching/macro approach? Though part of me wouldn't be surprised if functions were actually transformed into some version of macros to allow features like Listable to be implemented. The reason I care about this question is because of the recent set of questions (1) (2) about trying to catch Mathematica errors in large programs. If most of the computations were defined in terms of Functions, it seems to me that keeping track of the order of evaluation and where the error originated would be easier than trying to catch the error after the input has been rewritten by the successive application of macros/patterns.

  Read the article

• How to use V8's built in functions

  - by Victor jiang

  I'm new in both javascript and V8. According to Google's Embedder's Guide, I saw something in the context section talking about built-in utility javascript functions. And I also found some .js files(e.g. math.js) in the downloaded source code, so I tried to write a simple program to call functions in these files, but I failed. Does a context created by Persistent<Context> context = Context::New() have any built-in js functions? How can I access them? Is there a way to first import existing js files as a library(something like src="xxx" type="text/javascript" in HTML page) and then run my own execute script? Can I call google maps api through the embedded V8 library in app? How?

  Read the article

• Rails scalar query

  - by Craig

  I need to display a UI element (e.g. a star or checkmark) for employees that are 'favorites' of the current user (another employee). The Employee model has the following relationship defined to support this: has_and_belongs_to_many :favorites, :class_name => "Employee", :join_table => "favorites", :association_foreign_key => "favorite_id", :foreign_key => "employee_id" The favorites has two fields: employee_id, favorite_id. If I were to write SQL, the following query would give me the results that I want: SELECT id, account, IF( ( SELECT favorite_id FROM favorites WHERE favorite_id=p.id AND employee_id = ? ) IS NULL, FALSE, TRUE) isFavorite FROM employees Where the '?' would be replaced by the session[:user_id]. How do I represent the isFavorite scalar query in Rails? Another approach would use a query like this: SELECT id, account, IF(favorite_id IS NULL, FALSE, TRUE) isFavorite FROM employees e LEFT OUTER JOIN favorites f ON e.id=f.favorite_id AND employee_id = ? Again, the '?' is replaced by the session[:user_id] value. I've had some success writing this in Rails: ee=Employee.find(:all, :joins=>"LEFT OUTER JOIN favorites ON employees.id=favorites.favorite_id AND favorites.employee_id=1", :select=>"employees.*,favorites.favorite_id") Unfortunately, when I try to make this query 'dynamic' by replacing the '1' with a '?', I get errors. ee=Employee.find(:all, :joins=>["LEFT OUTER JOIN favorites ON employees.id=favorites.favorite_id AND favorites.employee_id=?",1], :select=>"employees.*,favorites.favorite_id") Obviously, I have the syntax wrong, but can :joins expressions be 'dynamic'? Is this a case for a Lambda expression? I do hope to add other filters to this query and use it with will_paginate and acts_as_taggable_on, if that makes a difference. edit errors from trying to make :joins dynamic: ActiveRecord::ConfigurationError: Association named 'LEFT OUTER JOIN favorites ON employees.id=favorites.favorite_id AND favorites.employee_id=?' was not found; perhaps you misspelled it? from /Users/craibuc/.gem/ruby/1.8/gems/activerecord-2.3.5/lib/active_record/associations.rb:1906:in `build' from /Users/craibuc/.gem/ruby/1.8/gems/activerecord-2.3.5/lib/active_record/associations.rb:1911:in `build' from /Users/craibuc/.gem/ruby/1.8/gems/activerecord-2.3.5/lib/active_record/associations.rb:1910:in `each' from /Users/craibuc/.gem/ruby/1.8/gems/activerecord-2.3.5/lib/active_record/associations.rb:1910:in `build' from /Users/craibuc/.gem/ruby/1.8/gems/activerecord-2.3.5/lib/active_record/associations.rb:1830:in `initialize' from /Users/craibuc/.gem/ruby/1.8/gems/activerecord-2.3.5/lib/active_record/base.rb:1789:in `new' from /Users/craibuc/.gem/ruby/1.8/gems/activerecord-2.3.5/lib/active_record/base.rb:1789:in `add_joins!' from /Users/craibuc/.gem/ruby/1.8/gems/activerecord-2.3.5/lib/active_record/base.rb:1686:in `construct_finder_sql' from /Users/craibuc/.gem/ruby/1.8/gems/activerecord-2.3.5/lib/active_record/base.rb:1548:in `find_every' from /Users/craibuc/.gem/ruby/1.8/gems/activerecord-2.3.5/lib/active_record/base.rb:615:in `find'

  Read the article

• GCC (ld) option to strip unreferenced data/functions

  - by legends2k

  I've written an program which uses a library which has numerous functuions, but I only limited functions from it. GCC is the compiler I use. Once I've created a binary, when I used nm to see the symbols in it, it shows all the unwanted (unreferenced) functions which are never used. How do I removed those unreferenced functions and data from the executable? Is the -s option right? I'm tols that it strips all symbol table and relocation data from the binary, but does this remove the function and data too? I'm not sure on how to verify this too, since after using -s nm doesn't work since it's stripped all sym. table data too.

  Read the article

• bash bcmath functions

  - by Gordon

  I have two functions for GNU bc in a Bash script. BC_CEIL="define ceil(x) { if (x>0) { if (x%1>0) return x+(1-(x%1)) else return x } else return -1*floor(-1*x) }\n" BC_FLOOR="define floor(x) { if (x>0) return x-(x%1) else return -1*ceil(-1*x) }\n" echo -e "scale=2"$BC_CEIL$BC_FLOOR"ceil(2.5)" | bc Both functions work fine in interactive bc. bc does not seem to allow multiple functions on one line separated by ; though, so I have to echo -n | bc with newlines at the end of each function. The above output is 2.5, not the expected 3.0 that I get if I type it into bc -i myself. It seems that bash calls bc for each line of echo output, rather than echo'ing it all to a single instance. Is there any workaround for this?

  Read the article

< Previous Page | 19 20 21 22 23 24 25 26 27 28 29 30  | Next Page >