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When should I use nil and NULL in Objective-C?
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technically, they are exactly equal, you can send messages to both nil and to NULL. Idiomatically though nil is usually used to represent an object
– cobbal
Oct 14 '09 at 5:43
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What's the difference between SortedList and SortedDictionary?
...<TKey,TValue> ? Are there any circumstances where you would specifically use one and not the other?
7 Answers
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Python Dictionary Comprehension
...>> print d
{0: 0, 1: 1, 2: 4, 3: 9, 4: 16}
If you want to set them all to True:
>>> d = {n: True for n in range(5)}
>>> print d
{0: True, 1: True, 2: True, 3: True, 4: True}
What you seem to be asking for is a way to set multiple keys at once on an existing dictionary. ...
Why can't I use a list as a dict key in python?
..., with the hash as, say, their memory location?
It can be done without really breaking any of the requirements, but it leads to unexpected behavior. Lists are generally treated as if their value was derived from their content's values, for instance when checking (in-)equality. Many would - underst...
Practical usage of setjmp and longjmp in C
...n me where exactly setjmp() and longjmp() functions can be used practically in embedded programming? I know that these are for error handling. But I'd like to know some use cases.
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What is the common header format of Python files?
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Its all metadata for the Foobar module.
The first one is the docstring of the module, that is already explained in Peter's answer.
How do I organize my modules (source files)? (Archive)
The first line of each file shoud be #!/us...
Where is my Django installation?
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Current top (accepted) answer works with my Ubuntu installation. As does yours. As do all of them!
– Adam Marshall
Apr 28 '14 at 14:24
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Replace multiple characters in one replace call
... just have to chain. However, you could add a prototype:
String.prototype.allReplace = function(obj) {
var retStr = this;
for (var x in obj) {
retStr = retStr.replace(new RegExp(x, 'g'), obj[x]);
}
return retStr;
};
console.log('aabbaabbcc'.allReplace({'a': 'h', 'b': 'o'}))...
What new capabilities do user-defined literals add to C++?
C++11 introduces user-defined literals which will allow the introduction of new literal syntax based on existing literals ( int , hex , string , float ) so that any type will be able to have a literal presentation.
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How to check if all elements of a list matches a condition?
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The best answer here is to use all(), which is the builtin for this situation. We combine this with a generator expression to produce the result you want cleanly and efficiently. For example:
>>> items = [[1, 2, 0], [1, 2, 0], [1, 2, 0]]
>>...