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Hidden Features of PHP? [closed]
...and getting a reference most of the time is great.
– Allain Lalonde
Sep 14 '08 at 17:46
1
This is...
Python - Create a list with initial capacity
...bject %d" % ( i, )
result.append(message)
return result
def doAllocate( size=10000 ):
result=size*[None]
for i in range(size):
message= "some unique object %d" % ( i, )
result[i]= message
return result
Results. (evaluate each function 144 times and average ...
When would anyone use a union? Is it a remnant from the C-only days?
I have learned but don't really get unions. Every C or C++ text I go through introduces them (sometimes in passing), but they tend to give very few practical examples of why or where to use them. When would unions be useful in a modern (or even legacy) case? My only two guesses would be programming ...
What __init__ and self do on Python?
...to declare it explicitly. When you create an instance of the A class and call its methods, it will be passed automatically, as in ...
a = A() # We do not pass any argument to the __init__ method
a.method_a('Sailor!') # We only pass a single argument
The __init__ method is roughly w...
Creating C macro with ## and __LINE__ (token concatenation with positioning macro)
...lizing) unless the result needs to be "stringified". Gcc has features but ALL can be done with plain C version 1 (and some argue Berkeley 4.3 C is so much faster it's worth learning how to use).
**Clang (llvm) DOES NOT DO WHITE SPACE CORRECTLY for macro expansion - it adds whitespace (which certai...
StringBuilder vs String concatenation in toString() in Java
...o builder?
At the point where you're concatenating in a loop - that's usually when the compiler can't substitute StringBuilder by itself.
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foll...
Count character occurrences in a string in C++
...
Small note, but the return type is typically signed. For some reason std::count returns type iterator_traits<InputIt>::difference_type, which for most standard containers is std::ptrdiff_t, not std::size_t.
...
Performance difference for control structures 'for' and 'foreach' in C#
...t will depend on whether you're doing any real work in the loop. In almost all cases, the difference to performance won't be significant, but the difference to readability favours the foreach loop.
I'd personally use LINQ to avoid the "if" too:
foreach (var item in list.Where(condition))
{
}
EDI...
Objective-C : BOOL vs bool
..., you can assume that BOOL is a char. You can use the (C99) bool type, but all of Apple's Objective-C frameworks and most Objective-C/Cocoa code uses BOOL, so you'll save yourself headache if the typedef ever changes by just using BOOL.
...
Link to all Visual Studio $ variables
...
Now if only there were a way to access these programmatically in our code (in my case C#).
– Chiramisu
Feb 22 at 7:52
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