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What does a \ (backslash) do in PHP (5.3+)?
...mbol is used in namespaces. It is the start symbol to indicate a namespace and also serves as a separator between sub-namespace names.
See official documentation about
namespacing.
Opcache
Additionally in PHP 7.0+ some functions are replaced with opcodes by OPCache, which makes these specific fu...
ORA-00979 not a group by expression
...ults to a single value (like MIN, MAX or SUM).
A simple example to understand why this happens: Imagine you have a database like this:
FOO BAR
0 A
0 B
and you run SELECT * FROM table GROUP BY foo. This means the database must return a single row as result with the first column 0 to fulfill t...
Can “git pull --all” update all my local branches?
I often have at least 3 remote branches: master, staging and production. I have 3 local branches that track those remote branches.
...
Getting the last element of a list
...
some_list[-1] is the shortest and most Pythonic.
In fact, you can do much more with this syntax. The some_list[-n] syntax gets the nth-to-last element. So some_list[-1] gets the last element, some_list[-2] gets the second to last, etc, all the way down t...
Is \d not supported by grep's basic expressions?
...
grep's default mode is (iirc) POSIX regex, and \d is pcre. You can either pass -P to gnu grep, for perl-like regexps, or use [[:digit:]] instead of \d.
daenyth@Bragi ~ $ echo 1 | grep -P '\d'
1
daenyth@Bragi ~ $ echo 1 | grep '[[:digit:]]'
1
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How do I remove a substring from the end of a string in Python?
...t mean "remove this substring". x.strip(y) treats y as a set of characters and strips any characters in that set from the ends of x.
Instead, you could use endswith and slicing:
url = 'abcdc.com'
if url.endswith('.com'):
url = url[:-4]
Or using regular expressions:
import re
url = 'abcdc.co...
Check if a value is within a range of numbers
... answered Apr 9 '18 at 2:51
AlexanderAlexander
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In R, how to get an object's name after it is sent to a function?
...ion when a set of list items are passed from the first argument to lapply (and it also fails when an object is passed from a list given to a for-loop.) You would be able to extract the ".Names"-attribute and the order of processing from the structure result, if it were a named vector that were being...
How to post JSON to PHP with curl
...way off base, but I've been trying all afternoon to run the curl post command in this recess PHP framework tutorial. What I don't understand is how is PHP supposed to interpret my POST, it always comes up as an empty array.
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XML Document to String
...
and the writer.getBuffer().toString() can just be writer.toString()
– bvdb
Jun 1 '17 at 10:23
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