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not None test in Python [duplicate]
...r of the latter two, since val could potentially be of a type that defines __eq__() to return true when passed None.
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What is a singleton in C#?
...Prevent outside instantiation
}
private static readonly Singleton _singleton = new Singleton();
public static Singleton GetSingleton()
{
return _singleton;
}
}
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C library function to perform sort
... changed as per most suggestions. I draw the line, @ChrisL, at needing size_t since my arrays never get that big :-) And, @AndreyT, clever though that hack is, I prefer my code to be readable :-)
– paxdiablo
Nov 24 '09 at 11:44
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How to get Scala List from Java List?
...now built into the language using:
import scala.collection.JavaConversions._
...
lst.toList.foreach{ node => .... }
works. asScala did not work
In 2.12.x use import scala.collection.JavaConverters._
In 2.13.x use import scala.jdk.CollectionConverters._
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how to return index of a sorted list? [duplicate]
...ray([2,3,1,4,5])
>>> vals
array([2, 3, 1, 4, 5])
>>> sort_index = numpy.argsort(vals)
>>> sort_index
array([2, 0, 1, 3, 4])
If not available, taken from this question, this is the fastest method:
>>> vals = [2,3,1,4,5]
>>> sorted(range(len(vals)), key=...
Get file version in PowerShell
...s:
get-childitem * -include *.dll,*.exe | foreach-object { "{0}`t{1}" -f $_.Name, [System.Diagnostics.FileVersionInfo]::GetVersionInfo($_).FileVersion }
Or even nicer as a script: https://jtruher3.wordpress.com/2006/05/14/powershell-and-file-version-information/
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Check that an email address is valid on iOS [duplicate]
...ing-an-e-mail-address/
NSString *stricterFilterString = @"^[A-Z0-9a-z\\._%+-]+@([A-Za-z0-9-]+\\.)+[A-Za-z]{2,4}$";
NSString *laxString = @"^.+@([A-Za-z0-9-]+\\.)+[A-Za-z]{2}[A-Za-z]*$";
NSString *emailRegex = stricterFilter ? stricterFilterString : laxString;
NSPredicate *emailTest = [NS...
How to set the prototype of a JavaScript object that has already been instantiated?
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EDIT Feb. 2012: the answer below is no longer accurate. __proto__ is being added to ECMAScript 6 as "normative optional" which means it isn't required to be implemented but if it is, it must follow the given set of rules. This is currently unresolved but at least it will be offici...
Accurate way to measure execution times of php scripts
...otime — Return current Unix timestamp with microseconds
If get_as_float is set to TRUE, then microtime() returns a float, which represents the current time in seconds since the Unix epoch accurate to the nearest microsecond.
Example usage:
$start = microtime(true);
while (...) {
}
$...
Any way to delete in vim without overwriting your last yank? [duplicate]
...
Pass to the _ register, the black hole.
To delete a line without sticking it in the registers:
"_dd
See also :help registers.
It's probably safest, if you want to paste something over and over again, to yank it into a "named" regist...