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Should I use 'has_key()' or 'in' on Python dicts?
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in is definitely more pythonic.
In fact has_key() was removed in Python 3.x.
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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:
•...
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...
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...
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, ...
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...
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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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.
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How to maintain aspect ratio using HTML IMG tag
... The size is fixed, the aspect ratio is not, as the question was specifically about any image of any resolution. Including resolutions smaller than 64x64.
– Koenigsberg
Jul 31 '18 at 8:50
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