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Is there a null-coalescing (Elvis) operator or safe navigation operator in javascript?
...e expression is null, but also when it's undefined, false, 0, or the empty string.
– Cameron
Jul 7 '11 at 16:41
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Useful code which uses reduce()? [closed]
...found for it besides + and * were with and and or, but now we have any and all to replace those cases.
foldl and foldr do come up in Scheme a lot...
Here's some cute usages:
Flatten a list
Goal: turn [[1, 2, 3], [4, 5], [6, 7, 8]] into [1, 2, 3, 4, 5, 6, 7, 8].
reduce(list.__add__, [[1, 2, 3]...
How to copy to clipboard in Vim?
... As an addendum to your note - you may also have to install extra packages to get this to work. If your vim lacks the +xterm_clipboard feature (visible when you run vim --version). This was the case for me (running Kubuntu 12.10). I had to install the vim-gui-common package to get the...
Change default timeout for mocha
... enter this (i.e. "--timeout 10000") under Run->Edit Configurations->Extra Mocha Options.
– Rubicon
Dec 8 '16 at 19:22
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使用App Inventor扩展实现多点触控：Rotation Detector · App Inventor 2 中文网
...alizeAngle((float) Math.atan2(v2y, v2x),v2x,v2y);
Log.i("Rotate", String.format("Vector1 (%f,%f) Vector2 (%f,%f)", v1x,v1y,v2x,v2y));
float angle = (float)Math.toDegrees(angle1-angle2);
return angle;
}
private float normalizeAngle(float angle,float x, float y){
...
Running a Python script from PHP
...unction:
Execute command via shell and return the complete output as a string.
It returns the output from the executed command or NULL if an error
occurred or the command produces no output.
<?php
$command = escapeshellcmd('/usr/custom/test.py');
$output = shell_exec($command);
ech...
In php, is 0 treated as empty?
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The following things are considered to be empty:
"" (an empty string)
0 (0 as an integer)
0.0 (0 as a float)
"0" (0 as a string)
NULL
FALSE
array() (an empty array)
var $var; (a variable declared, but without a value in a class)
Note that this is exactly the same list...
How do I print the elements of a C++ vector in GDB?
...o have gdb 7 (I tested it on gdb 7.01) and some python pretty-printer. Installation process of these is described on gdb wiki.
What is more, after installing above, this works well with Eclipse C++ debugger GUI (and any other IDE using GDB, as I think).
...
What does __FILE__ mean in Ruby?
I see this all the time in Ruby:
4 Answers
4
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Chrome, Javascript, window.open in new tab
...pup’) by specifying options in the 3rd parameter
3. If the window.open call was not part of a user-initiated event, it’ll open in a new window.
4. A “user initiated event” does not have to the same function call – but it must originate in the function invoked by a user click
5. If a use...