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How do I show/hide a UIBarButtonItem?
I created a toolbar in IB with several buttons. I would like to be able to hide/show one of the buttons depending on the state of the data in the main window.
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Performance of FOR vs FOREACH in PHP
...he context. Personally I almost never use for for array traversal. I use it for other types of iteration, but foreach is just too easy... The time difference is going to be minimal in most cases.
The big thing to watch for is:
for ($i = 0; $i < count($array); $i++) {
That's an expensive lo...
Should I put #! (shebang) in Python scripts, and what form should it take?
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The shebang line in any script determines the script's ability to be executed like a standalone executable without typing python beforehand in the terminal or when double clicking it in a file manager (when configured properly). It isn't necessary but generally put there so when some...
Understanding how recursive functions work
As the title explains I have a very fundamental programming question which I have just not been able to grok yet. Filtering out all of the (extremely clever) "In order to understand recursion, you must first understand recursion." replies from various online threads I still am not quite getting it....
Task vs Thread differences [duplicate]
...d is a lower-level concept: if you're directly starting a thread, you know it will be a separate thread, rather than executing on the thread pool etc.
Task is more than just an abstraction of "where to run some code" though - it's really just "the promise of a result in the future". So as some diff...
Close and Dispose - which to call?
...ering for classes such as SqlConnection or one of the several classes inheriting from the Stream class does it matter if I close Dispose rather than Close?
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Do I really need to encode '&' as '&'?
I'm using an ' & ' symbol with HTML5 and UTF-8 in my site's <title> . Google shows the ampersand fine on its SERPs, as do all the browsers in their titles.
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Accessing localhost (xampp) from another computer over LAN network - how to?
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Localhost is just a name given for the loopback, eg its like referring to yourself as "me" ..
To view it from other computers, chances are you need only do http://192.168.1.56 or http://myPcsName if that doesnt work, there is a chance that there is a firewall running on your ...
Why em instead of px?
I heard you should define sizes and distances in your stylesheet with em instead of in pixels. So the question is why should I use em instead of px when defining styles in css? Is there a good example that illustrates this?
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What does a Ajax call response like 'for (;;); { json data }' mean? [duplicate]
...I'm confused on the for (;;); part in the beginning of response. What is it used for?
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