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Using 'return' in a Ruby block
...y 1.9.1 for an embedded scripting language, so that "end-user" code gets written in a Ruby block. One issue with this is that I'd like the users to be able to use the 'return' keyword in the blocks, so they don't need to worry about implicit return values. With this in mind, this is the kind of th...
Is there a performance difference between i++ and ++i in C++?
...f you don't have a specific reason to use i++.]
For C++, the answer is a bit more complicated.
If i is a simple type (not an instance of a C++ class), then the answer given for C ("No there is no performance difference") holds, since the compiler is generating the code.
However, if i is an instan...
Why does this loop produce “warning: iteration 3u invokes undefined behavior” and output more than 4
...ned behaviour. And this means anything can happen, and discussing why does it happen under the rules of C++ doesn't make sense.
C++11 draft N3337: §5.4:1
If during the evaluation of an expression, the result is not mathematically defined or not in the range of
representable values for its t...
Is Python strongly typed?
... of a value doesn't change in unexpected ways. A string containing only digits doesn't magically become a number, as may happen in Perl. Every change of type requires an explicit conversion.
Dynamic typing means that runtime objects (values) have a type, as opposed to static typing where variables h...
What does the question mark and the colon (?: ternary operator) mean in objective-c?
...rnary operator (Objective-C is a superset of C):
label.frame = (inPseudoEditMode) ? kLabelIndentedRect : kLabelRect;
is semantically equivalent to
if(inPseudoEditMode) {
label.frame = kLabelIndentedRect;
} else {
label.frame = kLabelRect;
}
The ternary with no first element (e.g. variable ?:...
What makes Scala's operator overloading “good”, but C++'s “bad”?
...Thing(tm), and a mistake not to be repeated in newer languages. Certainly, it was one feature specifically dropped when designing Java.
...
HorizontalScrollView within ScrollView Touch Handling
...od to only intercept the touch event if the Y motion is > the X motion. It seems like the default behavior of a ScrollView is to intercept the touch event whenever there is ANY Y motion. So with the fix, the ScrollView will only intercept the event if the user is deliberately scrolling in the Y d...
WCF Error - Could not find default endpoint element that references contract 'UserService.UserServic
...
I had a run in with the same problem. My application was also a Silverlight application and the service was being called from a class library with a custom UserControl that was being used in it.
The solution is simple. Copy the endpoint ...
Can a CSS class inherit one or more other classes?
...r for so long and not knowing the answer to this question, I actually hope it's possible and I just didn't know about rather than what I think is the answer (which is that it's not possible).
...
Can one do a for each loop in java in reverse order?
...
The Collections.reverse method actually returns a new list with the elements of the original list copied into it in reverse order, so this has O(n) performance with regards to the size of the original list.
As a more efficient solution, you could write a decorator that presents a rev...