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Dictionaries and default values
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You can also use the defaultdict like so:
from collections import defaultdict
a = defaultdict(lambda: "default", key="some_value")
a["blabla"] => "default"
a["key"] => "some_value"
You can pass any ordinary function instead of lambda:
from collections import...
How do I revert an SVN commit?
.... seem to have worked. I think I understand: You need to merge the version from 'before' the 'bad' commit into your working repository. This is ok when you want to do a simple 'revert' of the previous commit. But what if you want to revert the changes made with version 1900?
– ...
Simulate delayed and dropped packets on Linux
...ys in increments of 10 ms. On 2.6, the value is a configuration parameter from 1000 to 100 Hz.
Later examples just change parameters without reloading the qdisc
Real wide area networks show variability so it is possible to add random variation.
# tc qdisc change dev eth0 root netem dela...
Is there any way to see the file system on the iOS simulator?
...tors (4.0, 4.1, 5.0, etc) you have ever run, go to the one you are running from in Xcode.
Once in a folder, go to Applications, choose the Finder option that shows date for files, and sort by date. Your application will be the most recent since it just changed the directory...
Inside the director...
Enabling error display in PHP via htaccess only
...p_value error_reporting <integer>
Combined with the integer values from this page: http://php.net/manual/en/errorfunc.constants.php
Note if you use -1 for your integer, it will show all errors, and be future proof when they add in new types of errors.
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counting number of directories in a specific directory
...cusive in directories, -type d means directory, and wc -l means line count from given directory listing
– shiyani suresh
Jan 22 '16 at 0:33
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is there a Java equivalent to null coalescing operator (??) in C#? [duplicate]
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int y = firstNonNull(calculateNullableValue(), -1);
since it saves you from either calling the potentially expensive method twice or declaring a local variable in your code to reference twice.
share
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Perl flags -pe, -pi, -p, -w, -d, -i, -t?
...ion :-)
The command line switches are all detailed in perlrun. (available from the command line by calling perldoc perlrun)
Going into the options briefly, one-by-one:
-p: Places a printing loop around your command so that it acts on each
line of standard input. Used mostly so Perl can beat ...
How to force table cell content to wrap?
...as necessary to fill line boxes.
pre : This value prevents user agents from collapsing sequences of white space.
Lines are only broken at preserved newline characters.
nowrap : This value collapses white space as for normal, but suppresses line breaks within text.
pre-wrap : This val...
Error installing libv8: ERROR: Failed to build gem native extension
...uired the following to find the correct build (which uses the brew install from coding addicted's answer below) bundle config build.therubyracer --with-v8-dir=/usr/local/opt/v8-315
– iturgeon
Apr 17 '16 at 23:48
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