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Do I set properties to nil in dealloc when using ARC?
...
Short answer: no, you do not have to nil out properties in dealloc under ARC.
Long answer: You should never nil out properties in dealloc, even in manual memory management.
In MRR, you should release your ivars. Nilling out properties means calling setters, which may invoke code that...
boost::flat_map and its performance compared to map and unordered_map
...e, because your cache will not be warm, and your operation will likely be called just once. Therefore you need to benchmark using RDTSC, and time stuff calling them once only.
Intel has made a paper describing how to use RDTSC (using a cpuid instruction to flush the pipeline, and calling it at least...
Recommended way of making React component/div draggable
...React.createClass({
getDefaultProps: function () {
return {
// allow the initial position to be passed in as a prop
initialPos: {x: 0, y: 0}
}
},
getInitialState: function () {
return {
pos: this.props.initialPos,
dragging: false,
rel: null // position...
Python argparse ignore unrecognised arguments
Optparse, the old version just ignores all unrecognised arguments and carries on. In most situations, this isn't ideal and was changed in argparse. But there are a few situations where you want to ignore any unrecognised arguments and parse the ones you've specified.
...
Why declare unicode by string in python?
...cepted since is the most complete one :)
– Oscar Carballal
Jul 3 '10 at 4:38
2
The default source...
fatal: The current branch master has no upstream branch
...tly push a new branch?": git push -u origin master or git push -u origin --all), you need now to resolve the authentication issue.
That depends on your url (ssh as in 'git@github.com/yourRepo, or https as in https://github.com/You/YourRepo)
For https url:
If your account is protected by the two-f...
How do I provide custom cast support for my class?
...ou want users to have to cast it or whether you want it to happen automagically. Generally, one direction will always work, that's where you use implicit, and the other direction can sometimes fail, that's where you use explicit.
The syntax is like this:
public static implicit operator dbInt64(Byt...
How to prevent gcc optimizing some statements in C?
...eeds. This has the advantage of just applying to a single function and not all functions defined in the same file.
Usage example:
void __attribute__((optimize("O0"))) foo(unsigned char data) {
// unmodifiable compiler code
}
...
What does -D_XOPEN_SOURCE do/mean?
...ch one you need (if any) by looking at the man page for each function you call.
For example, man strdup says:
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
strdup(): _SVID_SOURCE || _BSD_SOURCE || _XOPEN_SOURCE >= 500
strndup(), strdupa(), strndupa():...
What is an existential type?
...hrough the Wikipedia article Existential types . I gathered that they're called existential types because of the existential operator (∃). I'm not sure what the point of it is, though. What's the difference between
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