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What are five things you hate about your favorite language? [closed]
...ld be matched to another NULL value. If you understand this (what also is called ternary logic) than you might understand the reason for introducing the "IS" operator for testing against NULL.
– Alex
Aug 26 '10 at 16:58
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Best way to test for a variable's existence in PHP; isset() is clearly broken
... This looks a bit ugly to me, but in the case where you're actually checking an array element, it makes much more sense: isset($foo[$bar]) becomes array_key_exists($bar, $foo)
– Arild
Aug 25 '14 at 14:12
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static linking only some libraries
How can I statically link only a some specific libraries to my binary when linking with GCC?
8 Answers
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Iterating over all the keys of a map
Is there a way to get a list of all the keys in a Go language map? The number of elements is given by len() , but if I have a map like:
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Python: fastest way to create a list of n lists
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The probably only way which is marginally faster than
d = [[] for x in xrange(n)]
is
from itertools import repeat
d = [[] for i in repeat(None, n)]
It does not have to create a new int object in every iteration and is about 15 % faster on my machine.
Edi...
How do you rename a MongoDB database?
... changes to every shard if the DB is sharded, plus the config servers have all the shard metadata in terms of namespaces with their full names.
There would be absolutely no way to do this on a live system.
To do it offline, it would require re-writing every single database file to accommod...
`Apache` `localhost/~username/` not working
...s:
<Directory "/Users/kevin/Sites/">
Options Indexes MultiViews
AllowOverride None
Require all granted
</Directory>
Make sure to restart the Apache server afterwards with:
sudo apachectl restart
share
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Generating a PNG with matplotlib when DISPLAY is undefined
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Important note: .use needs to be called before pyplot is imported. So if you are, for instance, just trying to import pyplot, you need to import matplotlib first, call use, and than import pyplot.
– seaotternerd
Nov 8 '1...
Render partial from different folder (not shared)
... partial (user control) from a different folder?
With preview 3 I used to call RenderUserControl with the complete path, but whith upgrading to preview 5 this is not possible anymore.
Instead we got the RenderPartial method, but it's not offering me the functionality I'm looking for.
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Check if a JavaScript string is a URL
...invalid group.
– Kjell
Jun 5 '15 at 16:13
2
With Firefox 52.0.2, testing with "long" strings (not...