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jQuery.inArray(), how to use it right?
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The right way of using inArray(x, arr) is not using it at all, and using instead arr.indexOf(x).
The official standard name is also more clear on the fact that the returned value is an index thus if the element passed is the first one you will get back a 0 (that is falsy in Javascr...
Difference in System. exit(0) , System.exit(-1), System.exit(1 ) in Java
...) and according to range:
1-127 are user defined codes (so generated by calling exit(n))
128-255 are codes generated by termination due to different unix signals like SIGSEGV or SIGTERM
But I don't think you should care while coding on Java, it's just a bit of information. It's useful if you pla...
Why should I use Google's CDN for jQuery?
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This is because:
It increases the parallelism available. (Most browsers will only download 3 or 4 files at a time from any given site.)
It increases the chance that there will be a cache-hit. (As more sites follow this practice, more users already have the fil...
Is there a way to make a PowerShell script work by double clicking a .ps1 file?
... @UjjwalSingh: -NoProfile is also helpful, since the profile can do all kinds of things that the script doesn't expect.
– Joey
Apr 3 '17 at 6:28
6
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Checking for an empty field with MySQL
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If you want to find all records that are not NULL, and either empty or have any number of spaces, this will work:
LIKE '%\ '
Make sure that there's a space after the backslash. More info here: http://dev.mysql.com/doc/refman/5.0/en/string-com...
How to implement has_many :through relationships with Mongoid and mongodb?
...uire multiple queries.
https://github.com/mongoid/mongoid/issues/544
Normally if you have a many-many relationship in a RDBMS you would model that differently in MongoDB using a field containing an array of 'foreign' keys on either side. For example:
class Physician
include Mongoid::Document
...
Difference between static and shared libraries?
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Shared libraries are .so (or in Windows .dll, or in OS X .dylib) files. All the code relating to the library is in this file, and it is referenced by programs using it at run-time. A program using a shared library only makes reference to the code that it uses in the shared library.
Static librar...
Can I install Python 3.x and 2.x on the same Windows computer?
I'm running Windows and the shell/OS automatically runs Python based on the registry settings when you run a program on the command line. Will this break if I install a 2.x and 3.x version of Python on the same machine?
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How do I handle too long index names in a Ruby on Rails ActiveRecord migration?
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answered Mar 26 '11 at 16:49
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How to validate an email address in PHP
...($email, FILTER_VALIDATE_EMAIL)) {
// invalid emailaddress
}
Additionally you can check whether the domain defines an MX record:
if (!checkdnsrr($domain, 'MX')) {
// domain is not valid
}
But this still doesn't guarantee that the mail exists. The only way to find that out is by sending ...