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Checking from shell script if a directory contains files
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The solutions so far use ls. Here's an all bash solution:
#!/bin/bash
shopt -s nullglob dotglob # To include hidden files
files=(/some/dir/*)
if [ ${#files[@]} -gt 0 ]; then echo "huzzah"; fi
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How to properly check if std::function is empty in C++11?
...'re not checking for an empty lambda, but whether the std::function has a callable target stored in it. The check is well-defined and works because of std::function::operator bool which allows for implicit conversion to bool in contexts where boolean values are required (such as the conditional expr...
What is a segmentation fault?
...ng to a read-only portion of the memory, etc. Segmentation fault is essentially the same in most languages that let you mess with the memory management, there is no principial difference between segfaults in C and C++.
There are many ways to get a segfault, at least in the lower-level languages suc...
Difference between Python datetime vs time modules
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the time module is principally for working with unix time stamps; expressed as a floating point number taken to be seconds since the unix epoch. the datetime module can support many of the same operations, but provides a more object oriented set of t...
Select something that has more/less than x character
...e LENGTH function to the EmployeeName column). In Oracle, and probably in all other RDBMSs, this means that a regular index on EmployeeName will be useless to answer this query; the database will do a full table scan, which can be really costly.
However, various databases offer a function indexes ...
See “real” commit date in github (hour/day)
...a <time> element with an iso value under its datetime attribute.
If all else fails, like it did for me, try inspecting the text.
Sample element:
<time datetime="2015-01-22T20:48:13Z" is="relative-time" title="Jan 22, 2015, 2:48 PM CST">7 days ago</time>
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How does IPython's magic %paste work?
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You actually can copy code to IPython directly: you may have to first disable auto-indentation by entering %autoindent.
– Eric O Lebigot
Jan 15 '13 at 3:51
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MySQL DISTINCT on a GROUP_CONCAT()
...d Jun 21 '10 at 9:47
Daniel Vassallo
301k6666 gold badges475475 silver badges424424 bronze badges
answered Jun 21 '10 at 9:41
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How to get a DOM Element from a JQuery Selector
...h:
$("table").get(0);
or more simply:
$("table")[0];
There isn't actually a lot you need this for however (in my experience). Take your checkbox example:
$(":checkbox").click(function() {
if ($(this).is(":checked")) {
// do stuff
}
});
is more "jquery'ish" and (imho) more concise. W...
How do I escape characters in c# comments?
...braries like charting, but not for in-house development where we work with all of the code. I'm sort of shocked that MSFT hasn't come up with a solution that supports developers better here. We have regions that dynamically expand/collapse code...why can't we have an in-place comment rendering tog...