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cleanest way to skip a foreach if array is empty [duplicate]

...t need: foreach ((array) $items as $item) { print $item; } Note: to all the people complaining about typecast, please note that the OP asked cleanest way to skip a foreach if array is empty (emphasis is mine). A value of true, false, numbers or strings is not considered empty. In addition, th...
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Where is Erlang used and why? [closed]

...ng in its SMS and authentication systems. • Motorola is using Erlang in call processing products in the public-safety industry. • Ericsson uses Erlang in its support nodes, used in GPRS and 3G mobile networks worldwide. The most popular open source Erlang applications include the following: •...
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Find lines from a file which are not present in another file [duplicate]

...le1 file2 Note that if file2 contains duplicate lines that don't exist at all in file1, fgrep will output each of the duplicate lines. Also note that my totally non-scientific tests on a single laptop for a single (fairly large) dataset showed Solution 1 (using comm) to be almost 5 times faster tha...
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How to intercept touches events on a MKMapView or UIWebView objects?

...lot of hackish programming that imperfectly duplicates Apple's code, especially in the case of multitouch. Here's what I do: Implement a gesture recognizer that cannot be prevented and that cannot prevent other gesture recognizers. Add it to the map view, and then use the gestureRecognizer's touc...
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What is the point of function pointers?

...nction pointers. I guess it may be useful in some cases (they exist, after all), but I can't think of a case where it's better or unavoidable to use a function pointer. ...
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Is there a way to ignore header lines in a UNIX sort?

...ific advantage of being able to selectively sort parts of a piped input. all the other methods suggested will only sort plain files which can be read multiple times. This works on anything. share | ...
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Continuously read from STDOUT of external process in Ruby

...iven by blender line by line to update a progress bar in a GUI. It's not really important that blender is the external process whose stdout I need to read. ...
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Django set field value after a form is initialized

...value after the form was submitted, you can use something like: if form.is_valid(): form.cleaned_data['Email'] = GetEmailString() Check the referenced docs above for more on using cleaned_data share | ...
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Should I use 'has_key()' or 'in' on Python dicts?

... in is definitely more pythonic. In fact has_key() was removed in Python 3.x. share | improve this answer | follow | ...
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How to drop a table if it exists?

...e an error if the table does not exist). Instead, for a permanent table you can use IF OBJECT_ID('dbo.Scores', 'U') IS NOT NULL DROP TABLE dbo.Scores; Or, for a temporary table you can use IF OBJECT_ID('tempdb.dbo.#T', 'U') IS NOT NULL DROP TABLE #T; SQL Server 2016+ has a better way, ...