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How to define a preprocessor symbol in Xcode

...is: constant_1=VALUE constant_2=VALUE Note that you don't need the '='s if you just want to #define a symbol, rather than giving it a value (for #ifdef statements) share | improve this answer ...
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Remove all subviews?

... situation is muddled up by the fact that NSView and UIView handle things differently. For NSView (desktop Mac development only), you can simply use the following: [someNSView setSubviews:[NSArray array]]; For UIView (iOS development only), you can safely use makeObjectsPerformSelector: because t...
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Limit number of characters allowed in form input text field

...of characters that will be accepted as input. This can be greater that specified by SIZE , in which case the field will scroll appropriately. The default is unlimited. <input type="text" maxlength="2" id="sessionNo" name="sessionNum" onkeypress="return isNumberKey(event)" /> However, thi...
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What is a Manifest in Scala and when do you need it?

Since Scala 2.7.2 there is something called Manifest which is a workaround for Java's type erasure. But how does Manifest work exactly and why / when do you need to use it? ...
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Build the full path filename in Python

... + filename_suffix) Keep in mind that os.path.join() exists only because different operating systems use different path separator characters. It smooths over that difference so cross-platform code doesn't have to be cluttered with special cases for each OS. There is no need to do this for file name...
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convert double to int

... You can use a cast if you want the default truncate-towards-zero behaviour. Alternatively, you might want to use Math.Ceiling, Math.Round, Math.Floor etc - although you'll still need a cast afterwards. Don't forget that the range of int is muc...
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What is the difference between an abstract function and a virtual function?

What is the difference between an abstract function and a virtual function? In which cases is it recommended to use virtual or abstract? Which one is the best approach? ...
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Is gcc std::unordered_map implementation slow? If so - why?

...m to be pointing to "fixes" to max_load_factor handling, which led to the difference in performance. – jxh Jul 24 '12 at 18:21 ...
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Getting a map() to return a list in Python 3.x

...t cases, this ends up saving memory, and should make things go faster. If all you're going to do is iterate over this list eventually, there's no need to even convert it to a list, because you can still iterate over the map object like so: # Prints "ABCD" for ch in map(chr,[65,66,67,68]): p...
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Highlight label if checkbox is checked

... If you have <div> <input type="checkbox" class="check-with-label" id="idinput" /> <label class="label-for-check" for="idinput">My Label</label> </div> you can do .check-with-label:checked...