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pip installing in global site-packages instead of virtualenv
...ackage in a virtualenv causes the package to be installed in the global site-packages folder instead of the one in the virtualenv folder. Here's how I set up Python3 and virtualenv on OS X Mavericks (10.9.1):
...
Command line to remove an environment variable from the OS level configuration
...e variable from the user environment (which is the default place setx puts it):
REG delete HKCU\Environment /F /V FOOBAR
If the variable is set in the system environment (e.g. if you originally set it with setx /M), as an administrator run:
REG delete "HKLM\SYSTEM\CurrentControlSet\Control\Sessi...
Why is #!/usr/bin/env bash superior to #!/bin/bash?
I've seen in a number of places, including recommendations on this site ( What is the preferred Bash shebang? ), to use #!/usr/bin/env bash in preference to #!/bin/bash . I've even seen one enterprising individual suggest using #!/bin/bash was wrong and bash functionality would be lost by doing...
When is layoutSubviews called?
...
I had a similar question, but wasn't satisfied with the answer (or any I could find on the net), so I tried it in practice and here is what I got:
init does not cause layoutSubviews to
be called (duh)
addSubview: causes
layoutSubviews to be called on the
view being adde...
Haskell Type vs Data Constructor
...alue is expected.
Data constructors
To make things simple, we can start with an example of a type that represents a colour.
data Colour = Red | Green | Blue
Here, we have three data constructors. Colour is a type, and Green is a constructor that contains a value of type Colour. Similarly, Red a...
Are there disadvantages to using a generic varchar(255) for all text-based fields?
...elds will ever come close to having 255 characters. (If you're wondering, it's this way because Ruby on Rails migrations map String fields to VARCHAR(255) by default and I never bothered to override it).
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What is the use of the ArraySegment class?
...egment<T> has become a lot more useful in .NET 4.5+ and .NET Core as it now implements:
IList<T>
ICollection<T>
IEnumerable<T>
IEnumerable
IReadOnlyList<T>
IReadOnlyCollection<T>
as opposed to the .NET 4 version which implemented no interfaces whatsoever.
The...
How to unset a JavaScript variable?
...al variable in JavaScript (actually a window property, but I don't think it matters) which was already populated by a previous script but I don't want another script that will run later to see its value or that it was even defined.
...
Is it worth using Python's re.compile?
Is there any benefit in using compile for regular expressions in Python?
26 Answers
26...
How can I break up this long line in Python?
...ow would you go about formatting a long line such as this? I'd like to get it to no more than 80 characters wide:
5 Answers...