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How to decide font color in white or black depending on background color?
...need to break the hex code into 3 pieces to get the individual red, green, and blue intensities. Each 2 digits of the code represent a value in hexadecimal (base-16) notation. I won't get into the details of the conversion here, they're easy to look up.
Once you have the intensities for the individ...
MySQL, Check if a column exists in a table with SQL
... query that will check if a specific table in MySQL has a specific column, and if not — create it. Otherwise do nothing. This is really an easy procedure in any enterprise-class database, yet MySQL seems to be an exception.
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Significance of a .inl file in C++
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.inl files are never mandatory and have no special significance to the compiler. It's just a way of structuring your code that provides a hint to the humans that might read it.
I use .inl files in two cases:
For definitions of inline functions...
Overflow-x:hidden doesn't prevent content from overflowing in mobile browsers
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Creating a site wrapper div inside the <body> and applying the overflow-x:hidden to the wrapper instead of the <body> or <html> fixed the issue.
It appears that browsers that parse the <meta name="viewport"> tag simply ignore overflow attributes on t...
Deleting queues in RabbitMQ
... about the data in management database; i.e. users, vhosts, messages etc., and neither about other queues, then you can reset via commandline by running the following commands in order:
WARNING: In addition to the queues, this will also remove any users and vhosts, you have configured on your Ra...
Proper way to rename solution (and directories) in Visual Studio
...1 to be Project2, using a text editor like NotePad.
Restart Visual Studio, and everything will work as before, but with the project in a different directory.
You can also see renaming solution manually or post which describes this manual process.
Advantages
You can make the directory within Win...
jQuery map vs. each
In jQuery, the map and each functions seem to do the same thing. Are there any practical differences between the two? When would you choose to use one instead of the other?
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Regex to match only letters
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Use a character set: [a-zA-Z] matches one letter from A–Z in lowercase and uppercase. [a-zA-Z]+ matches one or more letters and ^[a-zA-Z]+$ matches only strings that consist of one or more letters only (^ and $ mark the begin and end of a string respectively).
If you want to match other letters...
Sort Go map values by keys
...erating over a map with a range loop, the iteration order is
not specified and is not guaranteed to be the same from one iteration
to the next. Since Go 1 the runtime randomizes map iteration order, as
programmers relied on the stable iteration order of the previous
implementation. If you require a ...
Delete an element from a dictionary
... del/assignment/etc. means you're going from constant time to linear time, and also using linear space. For small dicts, this is not a problem. But if you're planning to make lots of copies of large dicts, you probably want a different data structure, like a HAMT (as described in this answer).
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