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Check if a string has white space
... "/" characters are sufficient.
/^\s+$/ is checking whether the string is ALL whitespace:
^ matches the start of the string.
\s+ means at least 1, possibly more, spaces.
$ matches the end of the string.
Try replacing the regex with /\s/ (and no quotes)
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onConfigurationChanged not getting called
... event. The problem is that the method, which I override, is not getting called when I change the orientation of the phone. Not getting called at all.
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How can I add a help method to a shell script?
... into a shell script? I would like to display a help message when a user calls myscript.sh -h .
6 Answers
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Quick way to list all files in Amazon S3 bucket?
...s of filenames in it. What's the easiest way to get a text file that lists all the filenames in the bucket?
27 Answers
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LINQ .Any VS .Exists - What's the difference?
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I later made a post in another thread where I listed all the Linq "equivalents" of the .NET 2 List<> instance methods.
– Jeppe Stig Nielsen
Dec 1 '15 at 8:44
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Count all occurrences of a string in lots of files with grep
...a bunch of log files. I need to find out how many times a string occurs in all files.
15 Answers
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'IF' in 'SELECT' statement - choose output value based on column values
...tp://dev.mysql.com/doc/refman/5.0/en/control-flow-functions.html.
Additionally, you could handle when the condition is null. In the case of a null amount:
SELECT id,
IF(type = 'P', IFNULL(amount,0), IFNULL(amount,0) * -1) as amount
FROM report
The part IFNULL(amount,0) means when amount ...
JPA: How to have one-to-many relation of the same Entity type
...em.persist(daughter);
em.getTransaction().commit();
}
In this case, all three entity instances must be persisted before transaction commit. If I fail to persist one of the entities in the graph of parent-child relationships, then an exception is thrown on commit(). On Eclipselink, this is a...
How to duplicate virtualenv
...is to use pip to generate a requirements file. A requirements file is basically a file that contains a list of all the python packages you want to install (or have already installed in case of file generated by pip), and what versions they're at.
To generate a requirements file, go into your origin...
Canary release strategy vs. Blue/Green
...old until someone flips a feature toggle. Breaking your application into small, independently releaseable services is another, since there is less to test and less that can break.
You need to do a canary release if you're not completely certain that the new version will function correctly in produc...