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What’s the best way to check if a file exists in C++? (cross platform)

...turns "true" on non-existent files on network shares: "\\machine\share\this_file_doesnt_exist" => true. Last time I checked was on boost 1.33, use caution... – rlerallut Nov 6 '08 at 12:54 ...
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Unique constraint on multiple columns

...ied from technet's documentation, is in the form of: CONSTRAINT constraint_name UNIQUE [ CLUSTERED | NONCLUSTERED ] ( column [ ASC | DESC ] [ ,...n ] ) Therefore, the resuting table definition would be: CREATE TABLE [dbo].[user]( [userID] [int] IDENTITY(1,1) NOT NULL, [fcode] [int] ...
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How do I detect whether a Python variable is a function?

...obj) If this is for Python 3.x but before 3.2, check if the object has a __call__ attribute. You can do this with: hasattr(obj, '__call__') The oft-suggested types.FunctionTypes approach is not correct because it fails to cover many cases that you would presumably want it to pass, like with bui...
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Do I need dependency injection in NodeJS, or how to deal with …?

...nnection.js: (be sure to choose a better name) var db = require('whichever_db_vendor_i_use'); module.exports.fetchConnection() = function() { //logic to test connection //do I want to connection pool? //do I need only one connection throughout the lifecyle of my application? ret...
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how to change any data type into a string in python

... you're writing your own class and you want str to work for you, add: def __str__(self): return "Some descriptive string" print str(myObj) will call myObj.__str__(). repr is a similar method, which generally produces information on the class info. For most core library object, repr produces ...
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How to perform Callbacks in Objective-C

...newer) option is to use blocks: @interface MyClass: NSObject { void (^_completionHandler)(int someParameter); } - (void) doSomethingWithCompletionHandler:(void(^)(int))handler; @end @implementation MyClass - (void) doSomethingWithCompletionHandler:(void(^)(int))handler { // NOTE: copyin...
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What is the difference between attribute and property? [closed]

... In Python... class X( object ): def __init__( self ): self.attribute def getAttr( self ): return self.attribute def setAttr( self, value ): self.attribute= value property_name= property( getAttr, setAttr ) A property is a s...
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How to manage client-side JavaScript dependencies? [closed]

...tion may help you Example: Client app project hierarchy: sampleapp |___ main.js |___ cs.js |___ require.js main.js is where you initialize your client application and configure require.js: require.config({ baseUrl: "/sampleapp", paths: { jquery: "libs/jquery", // Lo...
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Adding external library into Qt Creator project

...your lib files in the project directory, you can reference them with the $$_PRO_FILE_PWD_ variable, e.g.: LIBS += -L"$$_PRO_FILE_PWD_/3rdparty/libs/" -lpsapi share | improve this answer |...
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Read only the first line of a file?

...od (Python 2 docs, Python 3 docs): with open('myfile.txt') as f: first_line = f.readline() Some notes: As noted in the docs, unless it is the only line in the file, the string returned from f.readline() will contain a trailing newline. You may wish to use f.readline().strip() instead to rem...