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Cloning an Object in Node.js
...ion is now marked as deprecated in the documentation of Node.js:
The util._extend() method was never intended to be used outside of internal Node.js modules. The community found and used it anyway.
It is deprecated and should not be used in new code. JavaScript comes with very similar built-in func...
MySQL check if a table exists without throwing an exception
...PDO syntax for it, but this seems pretty straight-forward:
$result = mysql_query("SHOW TABLES LIKE 'myTable'");
$tableExists = mysql_num_rows($result) > 0;
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How to delete migration files in Rails 3
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I usually:
Perform a rake db:migrate VERSION=XXX on all environments, to the version before the one I want to delete.
Delete the migration file manually.
If there are pending migrations (i.e., the migration I removed was not the...
What are CN, OU, DC in an LDAP search?
...N = Common Name
OU = Organizational Unit
DC = Domain Component
These are all parts of the X.500 Directory Specification, which defines nodes in a LDAP directory.
You can also read up on LDAP data Interchange Format (LDIF), which is an alternate format.
You read it from right to left, the right-m...
Decoding and verifying JWT token using System.IdentityModel.Tokens.Jwt
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Within the package there is a class called JwtSecurityTokenHandler which derives from System.IdentityModel.Tokens.SecurityTokenHandler. In WIF this is the core class for deserialising and serialising security tokens.
The class has a ReadToken(String) method tha...
How to check that an object is empty in PHP?
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empty doesn't actually check if an array is empty, empty($var) equivalent to (!isset($var) || !$var). You can replace your empty($arr)s with !$arr since array() == FALSE
– Timothy Zorn
Aug 20 '15 at 18:35...
How can I check if a var is a string in JavaScript?
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Guys, I really would give an accepted answer to both of you, but I can't, all I can do is +1 to both, than give the accepted answer at who is more near to my specific problem, that I've not fully explained.
– vitt...
How to check for null in Twig?
... Notice: as Twig 2.x check for variable is equal to value like is_ sameas must be {% if var is same as(false) %} not {% if var is sameas(false) %} see Doc url => twig.symfony.com/doc/2.x/tests/sameas.html
– ahmed hamdy
Jul 15 '19 at 17:01
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find() with nil when there are no records
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Yes, just do:
Challenge.find_by_id(10)
For Rails 4 and 5:
Challenge.find_by(id: 10)
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Reading specific lines only
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with linecache.getlin('some_file', 4) I get the 4th line, not the 5th.
– Juan
Dec 11 '14 at 18:14
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