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Checking if a key exists in a JavaScript object?
...r, if you want to particularly test for properties of the object instance (and not inherited properties), use hasOwnProperty:
obj.hasOwnProperty("key") // true
For performance comparison between the methods that are in, hasOwnProperty and key is undefined, see this benchmark
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How do I completely uninstall Node.js, and reinstall from beginning (Mac OS X)
My version of node is always v0.6.1-pre even after I install brew node and NVM install v0.6.19.
28 Answers
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Is there a better way of writing v = (v == 0 ? 1 : 0); [closed]
I want to toggle a variable between 0 and 1. If it's 0 I want to set it to 1, else if it's 1 I want to set it to 0.
31 Answ...
Is char signed or unsigned by default?
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The book is wrong. The standard does not specify if plain char is signed or unsigned.
In fact, the standard defines three distinct types: char, signed char, and unsigned char. If you #include <limits.h> and then look at CHAR_MIN, you can find...
What does the C++ standard state the size of int, long type to be?
...es.
I know that it depends on the architecture (16 bits, 32 bits, 64 bits) and the compiler.
24 Answers
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How to create REST URLs without verbs?
...n restful URLs. I'm all for the restful approach of using URLs with nouns and not verbs don't understand how to do this.
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Different floating point result with optimization enabled - compiler bug?
The below code works on Visual Studio 2008 with and without optimization. But it only works on g++ without optimization (O0).
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How to use a switch case 'or' in PHP
...icated" statements, eg: to test if a value is "greater than 3", "between 4 and 6", etc. If you need to do something like that, stick to using if statements, or if there's a particularly strong need for switch then it's possible to use it back to front:
switch (true) {
case ($value > 3) :
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Lock, mutex, semaphore… what's the difference?
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A lock allows only one thread to enter the part that's locked and the lock is not shared with any other processes.
A mutex is the same as a lock but it can be system wide (shared by multiple processes).
A semaphore does the same as a mutex but allows x number of threads to enter, this...
Convert datetime to Unix timestamp and convert it back in python
I have dt = datetime(2013,9,1,11) , and I would like to get a Unix timestamp of this datetime object.
11 Answers
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