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“Notice: Undefined variable”, “Notice: Undefined index”, and “Notice: Undefined offset” using PHP
..., "", "0", null, false or [].
Example:
$o = [];
@$var = ["",0,null,1,2,3,$foo,$o['myIndex']];
array_walk($var, function($v) {
echo (!isset($v) || $v == false) ? 'true ' : 'false';
echo ' ' . (empty($v) ? 'true' : 'false');
echo "\n";
});
Test the above snippet in the 3v4l.org onlin...
Python: try statement in a single line
...annoys me)
– Brant
Mar 26 '10 at 16:36
@Brant, Okay, that situation is a bit different than checking if a variable is ...
Rename package in Android Studio
... |
edited Sep 9 at 13:55
answered Mar 17 '15 at 6:32
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What is the equivalent of Java's final in C#?
...o only allow a variable to be assigned once:
Java
public final double pi = 3.14; // essentially a constant
C#
public readonly double pi = 3.14; // essentially a constant
As a side note, the effect of the readonly keyword differs from that of the const keyword in that the readonly expression is eva...
Adding n hours to a date in Java?
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Nikita RybakNikita Rybak
63.3k2121 gold badges147147 silver badges170170 bronze badges
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PHPUnit assert that an exception was thrown?
...
573
<?php
require_once 'PHPUnit/Framework.php';
class ExceptionTest extends PHPUnit_Framework_Te...
What characters are forbidden in Windows and Linux directory names?
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Legorooj
2,03122 gold badges66 silver badges2525 bronze badges
answered Dec 29 '09 at 18:19
Dour High ArchDour Hi...
How to get number of rows using SqlDataReader in C#
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answered Sep 5 '09 at 13:25
Henk HoltermanHenk Holterman
230k2525 gold badges269269 silver badges448448 bronze badges
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Do I need to create indexes on foreign keys on Oracle?
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138
The foreign key constraint alone does not provide the index on Oracle - one must (and should) b...
Git Bash is extremely slow on Windows 7 x64
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