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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...
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...
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...
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...
What is Node.js' Connect, Express and “middleware”?
Despite knowing JavaScript quite well, I'm confused what exactly these three projects in Node.js ecosystem do. Is it something like Rails' Rack? Can someone please explain?
...
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...
What does !important mean in CSS?
...
It means, essentially, what it says; that 'this is important, ignore subsequent rules, and any usual specificity issues, apply this rule!'
In normal use a rule defined in an external stylesheet is overruled by a style define...