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Find out how much memory is being used by an object in Python [duplicate]
...and internal structures related to object types and garbage collection. Finally, some python objects have non-obvious behaviors. For instance, lists reserve space for more objects than they have, most of the time; dicts are even more complicated since they can operate in different ways (they have a ...
Why can't I use the 'await' operator within the body of a lock statement?
The await keyword in C# (.NET Async CTP) is not allowed from within a lock statement.
8 Answers
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static const vs #define
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Personally, I loathe the preprocessor, so I'd always go with const.
The main advantage to a #define is that it requires no memory to store in your program, as it is really just replacing some text with a literal value. It also has...
Convert a series of parent-child relationships into a hierarchical tree?
...o '</ul>';
}
}
You'll only save 8 iterations on a dataset as small as this but on bigger sets it could make a difference.
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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
}
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How to check if a map contains a key in Go?
...ring) and ok will receive a bool that will be set to true if "foo" was actually present in the map
evaluates ok, which will be true if "foo" was in the map
If "foo" is indeed present in the map, the body of the if statement will be executed and val will be local to that scope.
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Regular expression to allow spaces between words
I want a regular expression that prevents symbols and only allows letters and numbers. The regex below works great, but it doesn't allow for spaces between words.
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How to detect user inactivity in Android
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Selects Session Timeout to be 5 mins.
Does some operations on the app. (all in foreground)
Now User bring Myapp to background and starts some other app.
----> Count down timer starts and logs out user after 5 mins
OR user turns the screen OFF.
----> Count down timer starts and logs ou...
How should I print types like off_t and size_t?
...6, some_uint16_t);
They are listed in the manpage of inttypes.h.
Personally, I would just cast the values to unsigned long or long like another answer recommends. If you use C99, then you can (and should, of course) cast to unsigned long long or long long and use the %llu or %lld formats respect...
Is Java “pass-by-reference” or “pass-by-value”?
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Java is always pass-by-value.
Unfortunately, we never handle an object at all, instead juggling object-handles called references (which are passed by value of course). The chosen terminology and semantics easily confuse many beginners.
It goes like this:
public static void main(String[] args) {
...