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What do two question marks together mean in C#?
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It's the null coalescing operator, and quite like the ternary (immediate-if) operator. See also ?? Operator - MSDN.
FormsAuth = formsAuth ?? new FormsAuthenticationWrapper();
expands to:
FormsAuth = formsAuth != null ? formsAuth : new FormsAuthenticationWr...
Multiple levels of 'collection.defaultdict' in Python
...possibilities offered by collections.defaultdict , notably in readability and speed. I have put them to use with success.
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Android - Handle “Enter” in an EditText
I am wondering if there is a way to handle the user pressing Enter while typing in an EditText , something like the onSubmit HTML event.
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Why doesn't C have unsigned floats?
...If C++ did support it, then you would be sometimes using an unsigned float and not realizing that your performance has just been killed. If C++ supported it then every floating point operation would need to be checked to see if it is signed or not. And for programs that do millions of floating poi...
What is the intent of the methods getItem and getItemId in the Android class BaseAdapter?
I'm curious about the purpose of the methods getItem and getItemId in the class Adapter in the Android SDK.
6 Answers
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How do I achieve the theoretical maximum of 4 FLOPs per cycle?
...one this exact task before. But it was mainly to measure power consumption and CPU temperatures. The following code (which is fairly long) achieves close to optimal on my Core i7 2600K.
The key thing to note here is the massive amount of manual loop-unrolling as well as interleaving of multiplies a...
How fast is D compared to C++?
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To enable all optimizations and disable all safety checks, compile your D program with the following DMD flags:
-O -inline -release -noboundscheck
EDIT: I've tried your programs with g++, dmd and gdc. dmd does lag behind, but gdc achieves performance...
How to restart Activity in Android
How do I restart an Android Activity ? I tried the following, but the Activity simply quits.
21 Answers
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Use “ENTER” key on softkeyboard instead of clicking button
Hello
I've got a searched EditText and search Button . When I type the searched text, I'd like to use ENTER key on softkeyboard instead of search Button to activate search function.
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How do I get the type name of a generic type argument?
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Make sure to test it with MyMethod<int>>() and see what you get...you have to account for nullable types if you care for the underlying type in that scenario.
– GR7
Apr 5 '10 at 23:11
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