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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...
What is the JavaScript equivalent of var_dump or print_r in PHP? [duplicate]
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314
Most modern browsers have a console in their developer tools, useful for this sort of debuggin...
Reordering of commits
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answered Apr 29 '10 at 21:13
CascabelCascabel
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What is the preferred/idiomatic way to insert into a map?
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edited Nov 26 '10 at 18:37
user229044♦
202k3535 gold badges298298 silver badges309309 bronze badges
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Performance differences between debug and release builds
... need to compromise readability.
Constant folding. x = 1 + 2; becomes x = 3; This simple example is caught early by the compiler, but happens at JIT time when other optimizations make this possible.
Copy propagation. x = a; y = x; becomes y = a; This helps the register allocator make better deci...
How to overlay one div over another div
...s://appharbor.com/assets/images/stackoverflow-logo.png" height="20" width="32" />b
</div>
</div>
I would suggest learning about position: relative and child elements with position: absolute.
share
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Is it safe to remove selected keys from map within a range loop?
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edited May 18 '15 at 16:35
Dave C
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answered Apr...
Rails update_attributes without save?
...:08
Arel
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answered Aug 2 '12 at 17:54
Ajedi32Ajedi32
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What do pty and tty mean?
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231
"tty" originally meant "teletype" and "pty" means "pseudo-teletype".
In UNIX, /dev/tty* is any...
Targeting both 32bit and 64bit with Visual Studio in same solution/project
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83
Yes, you can target both x86 and x64 with the same code base in the same project. In general, th...