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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...
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 ...
What are the primary differences between Haskell and F#? [closed]
...et for comparisons between F# and Haskell but haven't found anything really definitive. What are the primary differences and why would I want to choose one over the other?
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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 trigger Autofill in Google Chrome?
...stion and one for which documentation is surprisingly hard to come by. Actually, in many cases you will find that the Chrome Autofill functionality "just works." For example, the following snippet of html produces a form which, at least for me (Chrome v. 18), is automatically filled after clicking i...
What is the most efficient way to store tags in a database?
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Actually I believe de-normalising the tags table might be a better way forward, depending on scale.
This way, the tags table simply has tagid, itemid, tagname.
You'll get duplicate tagnames, but it makes adding/removing/editing...