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Pretty-print C++ STL containers
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83
This solution was inspired by Marcelo's solution, with a few changes:
#include <iostream>...
isset() and empty() - what to use
...as been set to NULL
Your code would be fine as:
<?php
$var = '23';
if (!empty($var)){
echo 'not empty';
}else{
echo 'is not set or empty';
}
?>
For example:
$var = "";
if(empty($var)) // true because "" is considered empty
{...}
if(isset($var)) //tru...
How to disable “Save workspace image?” prompt in R?
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jan-glx
3,5592222 silver badges4545 bronze badges
answered Feb 14 '11 at 19:12
Joshua UlrichJoshua Ulrich
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Delete fork dependency of a GitHub repository
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answered Apr 17 '13 at 6:13
Thomas MoulardThomas Moulard
3,54122 gold badges1616 silver badges2626 bronze badges
...
Rails 4: List of available datatypes
...SchemaStatements.html#method-i-add_column
These are the same as with Rails 3.
If you use PostgreSQL, you can also take advantage of these:
:hstore
:json
:jsonb
:array
:cidr_address
:ip_address
:mac_address
They are stored as strings if you run your app with a not-PostgreSQL database.
Edit, 201...
How to view file history in Git?
...ciated revision specifier that is a hash key (e.g. 14b8d0982044b0c49f7a855e396206ee65c0e787 and b410ad4619d296f9d37f0db3d0ff5b9066838b39). To view the difference between two different commits, use git diff with the first few characters of the revision specifiers of both commits, like so:
# diff bet...
ping response “Request timed out.” vs “Destination Host unreachable”
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139
Destination Host Unreachable
This message indicates one of two problems: either the local syst...
Font size in CSS - % or em?
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Glenn SlavenGlenn Slaven
31.3k2424 gold badges105105 silver badges161161 bronze badges
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Django, creating a custom 500/404 error page
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answered Jul 13 '14 at 16:56
Aaron LelevierAaron Lelevier
15.1k99 gold badges5858 silver badges9797 bronze badges
...