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How do I append one string to another in Python?
...ugh memory to resize the string, the original
string object at *pv is deallocated, *pv is set to NULL, an "out of
memory" exception is set, and -1 is returned. Else (on success) 0 is
returned, and the value in *pv may or may not be the same as on input.
As always, an extra byte is alloc...
Does the C++ standard mandate poor performance for iostreams, or am I just dealing with a poor imple
...sing work. In your char[] array example, the array of the required size is allocated in advance. In your vector and ostringstream example you are forcing the objects to repeatedly allocate and reallocate and possibly copy data many times as the object grows.
With std::vector this is easly resolved...
What's the difference between deque and list STL containers?
...ime is linear if capacity is 10 and size is also 10. Its because it has to allocate and copy all the elements to new memory.
– aJ.
Apr 16 '10 at 3:25
5
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How to change the Push and Pop animations in a navigation based app
...s managed to complete this task.
For Push:
MainView *nextView=[[MainView alloc] init];
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];
[UIView setAnimationDuration:0.75];
[self.navigationController pushViewController:nextView animated:NO];
[UIV...
Objective-C class -> string like: [NSArray className] -> @“NSArray”
...
Class arrayClass = NSClassFromString (name);
id anInstance = [[arrayClass alloc] init];
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When should I use a struct instead of a class?
...hort-living. In such a case there is a good chance that the object will be allocated on the stack which is much more efficient than putting it on the managed heap. What is more the memory allocated by the object will be freed as soon as it goes outside its scope. In other words it's less work for Ga...
Java8 Lambdas vs Anonymous classes
...st don't try to use your counter from multiple threads. If you're going to allocate something on the heap and capture it in a lambda, you might as well use an AIC and add a field that you can mutate directly. Using a lambda this way can work, but why bother when you can use a real object?
...
Make first letter of a string upper case (with maximum performance)
...lternative char.ToUpper(s[0]) + s.Substring(1), is that only one string is allocated, whereas the Substring approach allocates a string for the substring, then a second string to compose the final result.
EDIT: Here is what this approach looks like, combined with the initial test from CarlosMuño...
Convert NSData to String?
...oding:(NSStringEncoding)encoding
Example:
NSString *myString = [[NSString alloc] initWithData:myData encoding:NSUTF8StringEncoding];
Remark: Please notice the NSData value must be valid for the encoding specified (UTF-8 in the example above), otherwise nil will be returned:
Returns nil if the ini...
How do I call ::std::make_shared on a class with only protected or private constructors?
... suitable to hold an object of type T, shall be well formed. A shall be an allocator (17.6.3.5). The copy constructor and destructor of A shall not throw exceptions.
Since the requirement is unconditionally specified in terms of that expression and things like scope aren't taken into account, I th...