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Creating a new dictionary in Python
I want to build a dictionary in Python. However, all the examples that I see are instantiating a dictionary from a list, etc . ..
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Change string color with NSAttributedString?
...
There is no need for using NSAttributedString. All you need is a simple label with the proper textColor. Plus this simple solution will work with all versions of iOS, not just iOS 6.
But if you needlessly wish to use NSAttributedString, you can do something like this:
...
Migration: Cannot add foreign key constraint
...signed();
$table->string('priority_name');
$table->smallInteger('rank');
$table->text('class');
$table->timestamps('timecreated');
});
Schema::table('priorities', function($table) {
$table->foreign('user_id')->references('id')->on('...
Do htmlspecialchars and mysql_real_escape_string keep my PHP code safe from injection?
... is effectively just a string escaping function. It is not a magic bullet. All it will do is escape dangerous characters in order that they can be safe to use in a single query string. However, if you do not sanitise your inputs beforehand, then you will be vulnerable to certain attack vectors.
Ima...
C++ equivalent of java's instanceof
...nceof) you'd better ask yourself whether it's a necessary thing. It's generally a sign of poor design.
Typical workarounds is putting the special behaviour for the class you are checking for into a virtual function on the base class or perhaps introducing something like a visitor where you can int...
How to write to a file in Scala?
...portance are Resource, ReadChars and WriteChars.
File - File is a File (called Path) API that is based on a combination of Java 7 NIO filesystem and SBT PathFinder APIs.
Path and FileSystem are the main entry points into the Scala IO File API.
import scalax.io._
val output:Output = Resourc...
Thread-safe List property
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ConcurrentBag doesn't implement IList and is not actually thread safe version of List
– Vasyl Zvarydchuk
Apr 3 '17 at 20:55
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What is the difference between String.Empty and “” (empty string)?
...ich makes string.Empty more efficient.
In version 2.0 and later of .NET, all occurrences of "" refer to the same string literal, which means "" is equivalent to .Empty, but still not as fast as .Length == 0.
.Length == 0 is the fastest option, but .Empty makes for slightly cleaner code.
See the ...
Learning Python from Ruby; Differences and Similarities
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[x*x for x in values if x > 15]
to get a new list of the squares of all values greater than 15. In Ruby, you'd have to write the following:
values.select {|v| v > 15}.map {|v| v * v}
The Ruby code doesn't feel as compact. It's also not as efficient since it first converts the values a...
How to set Python's default version to 3.x on OS X?
...n use command python, which will leaving the alias untouched, and works in all shells.
If you launch interpreters more often (I do), you can always create more aliases to add as well, i.e.:
alias 2='python2'
alias 3='python3'
Tip: For scripts, instead of using a shebang like:
#!/usr/bin/env p...