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Is explicitly closing files important?
In Python, if you either open a file without calling close() , or close the file but not using try - finally or the " with " statement, is this a problem? Or does it suffice as a coding practice to rely on the Python garbage-collection to close all files? For example, if one does this:
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detach all packages while working in R
...*) is not necessary but can be useful to prevent the NULL reply from vertically spamming the R window.
(edit: 9/20/2019) In version 3.6.1
It may be helpful to convert loaded only names(sessionInfo()$loadedOnly) to explicitly attached packages first, and then detach the packages, as so.
lapply(names(...
maximum value of int
...imum value. Same goes for the C macros/constants.
– dalle
Dec 31 '09 at 11:29
4
in C99 you can al...
Rails Root directory path?
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Personally I like the newer syntax: Rails.root / 'app' / 'assets' / 'images' / 'logo.png'
– Ajedi32
Feb 18 '16 at 17:13
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Python Sets vs Lists
...move the object creation now. The setup phase of the timeit loops is only called once (docs.python.org/2/library/timeit.html#timeit.Timer.timeit).
– Ellis Percival
Sep 30 '14 at 10:09
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Django rest framework, use different serializers in the same ModelViewSet
... like to provide two different serializers and yet be able to benefit from all the facilities of ModelViewSet :
6 Answers
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When do we need curly braces around shell variables?
...xpand the variable identified by foobar.
Curly braces are also unconditionally required when:
expanding array elements, as in ${array[42]}
using parameter expansion operations, as in ${filename%.*} (remove extension)
expanding positional parameters beyond 9: "$8 $9 ${10} ${11}"
Doing this every...
Mongoose subdocuments vs nested schema
...still have the same subdocument structure.
– Martin Hallén
Jul 9 '14 at 9:17
2
you should also c...
When do I use the PHP constant “PHP_EOL”?
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@Andre: How about anyone that writes apps to be installed, used and deployed by others? Are you suggesting these should all limit their "supported platforms" to *nix?
– Cylindric
Mar 4 '11 at 10:52
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How to ALTER multiple columns at once in SQL Server
.... Each statement means a new scan but if you could alter multiple columns, all altering could have been much quicker
– erikkallen
Sep 8 '16 at 6:31
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