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How to determine if object is in array [duplicate]
I need to determine if an object already exists in an array in javascript.
11 Answers
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Why is there no logical xor in JavaScript?
...ul, but in all my years of programming I have never needed a logical XOR.
If you have two boolean variables you can mimic XOR with:
if (a != b)
With two arbitrary variables you could use ! to coerce them to boolean values and then use the same trick:
if (!a != !b)
That's pretty obscure though...
What is the proper way to check if a string is empty in Perl?
I've just been using this code to check if a string is empty:
6 Answers
6
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Checking if a key exists in a JavaScript object?
How do I check if a particular key exists in a JavaScript object or array?
22 Answers
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Check number of arguments passed to a Bash script
I would like my Bash script to print an error message if the required argument count is not met.
10 Answers
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Default value of a type at Runtime [duplicate]
... only need to account for two cases:
object GetDefaultValue(Type t)
{
if (t.IsValueType)
return Activator.CreateInstance(t);
return null;
}
(Because value types always have a default constructor, that call to Activator.CreateInstance will never fail).
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ProcessStartInfo hanging on “WaitForExit”? Why?
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The problem is that if you redirect StandardOutput and/or StandardError the internal buffer can become full. Whatever order you use, there can be a problem:
If you wait for the process to exit before reading StandardOutput the process can bloc...
Is it better in C++ to pass by value or pass by constant reference?
...ecially true before the existence of move semantics. The reason is simple: if you passed by value, a copy of the object had to be made and, except for very small objects, this is always more expensive than passing a reference.
With C++11, we have gained move semantics. In a nutshell, move semantics...
The point of test %eax %eax [duplicate]
...P subtracts the operands and sets the flags. Namely, it sets the zero flag if the difference is zero (operands are equal).
TEST sets the zero flag, ZF, when the result of the AND operation is zero. If two operands are equal, their bitwise AND is zero when both are zero. TEST also sets the sign flag...
How do you tell if a string contains another string in POSIX sh?
I want to write a Unix shell script that will do various logic if there is a string inside of another string. For example, if I am in a certain folder, branch off. Could someone please tell me how to accomplish this? If possible I would like to make this not shell specific (i.e. not bash only) but i...