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Is it possible to create static classes in PHP (like in C#)?
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You can have static classes in PHP but they don't call the constructor automatically (if you try and call self::__construct() you'll get an error).
Therefore you'd have to create an initialize() function and call it in each method:
<?php
class Hello
{
private static...
What is the best way to create constants in Objective-C
...he file in the Reddit-Prefix.pch file to make the constants available to all the files. Is it a good way of doing things? Also, I've done my research and found several methods to create constants, but I don't know which one to use:
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How to abandon a hg merge?
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Ah that is a good detail to know... actually I'm going to delete my comment claiming leaving off -r . is the same
– Thymine
Mar 1 '16 at 15:56
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Perl flags -pe, -pi, -p, -w, -d, -i, -t?
...eem to be mostly made up of punctuation :-)
The command line switches are all detailed in perlrun. (available from the command line by calling perldoc perlrun)
Going into the options briefly, one-by-one:
-p: Places a printing loop around your command so that it acts on each
line of standard ...
Can PostgreSQL index array columns?
... to this question in the documentation. If a column is an array type, will all the entered values be individually indexed?
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Python argparse mutual exclusive group
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add_mutually_exclusive_group doesn't make an entire group mutually exclusive. It makes options within the group mutually exclusive.
What you're looking for is subcommands. Instead of prog [ -a xxxx | [-b yyy -c zzz]], you'd have:
p...
Understanding repr( ) function in Python
...gt;>> x
'foo'
So the name x is attached to 'foo' string. When you call for example repr(x) the interpreter puts 'foo' instead of x and then calls repr('foo').
>>> repr(x)
"'foo'"
>>> x.__repr__()
"'foo'"
repr actually calls a magic method __repr__ of x, which gives the s...
How to remove files and directories quickly via terminal (bash shell) [closed]
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rm -rf some_dir
-r "recursive"
-f "force" (suppress confirmation messages)
Be careful!
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Update multiple rows in same query using PostgreSQL
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This is wrong... You will update all rows, even if it is not '123' nor '345'. You should use WHERE column_b IN ('123','456')...
– MatheusOl
Sep 14 '13 at 3:54
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Is explicitly closing files important?
In Python, if you either open a file without calling close() , or close the file but not using try - finally or the " with " statement, is this a problem? Or does it suffice as a coding practice to rely on the Python garbage-collection to close all files? For example, if one does this:
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