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In Python how should I test if a variable is None, True or False

...follow | edited Oct 14 '15 at 20:13 answered Jan 7 '10 at 13:46 ...
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How to use LocalBroadcastManager?

... I'll answer this anyway. Just in case someone needs it. ReceiverActivity.java An activity that watches for notifications for the event named "custom-event-name". @Override public void onCreate(Bundle savedInstanceState) { ... // Register to receive messages. // We ...
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What are the benefits to marking a field as `readonly` in C#?

What are the benefits of having a member variable declared as read only? Is it just protecting against someone changing its value during the lifecycle of the class or does using this keyword result in any speed or efficiency improvements? ...
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How can I check if an element exists in the visible DOM?

How do you test an element for existence without the use of the getElementById method? 25 Answers ...
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How expensive is RTTI?

I understand that there is a resource hit from using RTTI, but how big is it? Everywhere I've looked just says that "RTTI is expensive," but none of them actually give any benchmarks or quantitative data reguarding memory, processor time, or speed. ...
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Detect encoding and make everything UTF-8

... If you apply utf8_encode() to an already UTF-8 string, it will return garbled UTF-8 output. I made a function that addresses all this issues. It´s called Encoding::toUTF8(). You don't need to know what the encoding of your strings is. It can be Latin1 (ISO 8859-1), Windows-125...
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Is memcached a dinosaur in comparison to Redis? [closed]

I have worked quite a bit with memcached the last weeks and just found out about Redis. When I read this part of their readme, I suddenly got a warm, cozy feeling in my stomach: ...
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Why are hexadecimal numbers prefixed with 0x?

... Short story: The 0 tells the parser it's dealing with a constant (and not an identifier/reserved word). Something is still needed to specify the number base: the x is an arbitrary choice. Long story: In the 60's, the prevalent programming number systems were d...
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How do I find the length of an array?

...f(a)/sizeof(*a)) << std::endl; This doesn't work on pointers (i.e. it won't work for either of the following): int *p = new int[7]; std::cout << "Length of array = " << (sizeof(p)/sizeof(*p)) << std::endl; or: void func(int *p) { std::cout << "Length of array ...
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Accessing constructor of an anonymous class

...I have a concrete class Class1 and I am creating an anonymous class out of it. 10 Answers ...