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How to check if a python module exists without importing it
I need to know if a python module exists, without importing it.
13 Answers
13
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Convert Base64 string to an image file? [duplicate]
...s. This will result in invalid image data when the base64 function decodes it. Remove that data in the function before decoding the string, like so.
function base64_to_jpeg($base64_string, $output_file) {
// open the output file for writing
$ifp = fopen( $output_file, 'wb' );
// split...
Is there a way to make GHC provide the type class constraints of typed holes?
It would be nice if GHC would also tell me that the typed hole has the Show type class constraint.
3 Answers
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Can you test google analytics on a localhost address?
...localhost. You can verify this by opening the developer tools in your favorite browser and watching the network requests during page load. If it is working you will see a request for _utm.gif in the network requests list.
Updated 2013 for Universal Analytics - analytics.js
Google released a new vers...
Do I need to disable NSLog before release Application?
When releasing an app for iPhone, if I disable NSLog(); will it perform better?
12 Answers
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How to make inline functions in C#
...return x + y;
};
Action<int> print = delegate(int x)
{
Console.WriteLine(x);
}
Action<int> helloWorld = delegate // parameters can be elided if ignored
{
Console.WriteLine("Hello world!");
}
Lambdas are new in C# 3.0 and come in two flavours.
Expression lambdas:
Func<int, ...
How can I maintain fragment state when added to the back stack?
I've written up a dummy activity that switches between two fragments. When you go from FragmentA to FragmentB, FragmentA gets added to the back stack. However, when I return to FragmentA (by pressing back), a totally new FragmentA is created and the state it was in is lost. I get the feeling I'm ...
What is a singleton in C#?
What is a Singleton and when should I use it?
16 Answers
16
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error C2780: \'void __cdecl std::sort(_RI,_RI,_Pr)\' : expects 3 argum...
error C2780: 'void __cdecl std::sort(_RI,_RI,_Pr)' : expects 3 arguments - 2 providedprog7.cpp(8) :error C2780:'void __cdecl std::sort(_RI,_RI,_Pr)' : expects 3 arguments - 2 provided C: Pr...prog7.cpp(8) : error C2780: 'void __cdecl std::sort(_RI,_RI,_Pr)' : expects 3 arguments - 2 provided
C:...
Why does GCC generate 15-20% faster code if I optimize for size instead of speed?
...nt instruction sequences, compiler optimizations enabled by -O2 might benefit average processor, but decrease performance on your particular processor (and the same applies to -Os). If you try the same example on different processors, you will find that on some of them benefit from -O2 while other a...