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Shell equality operators (=, ==, -eq)
...are equivalent, and in plain sh = is the only one guaranteed to work.
$ a=foo
$ [ "$a" = foo ]; echo "$?" # POSIX sh
0
$ [ "$a" == foo ]; echo "$?" # bash specific
0
$ [ "$a" -eq foo ]; echo "$?" # wrong
-bash: [: foo: integer expression expected
2
(Side note: Quote those variable ...
Does IMDB provide an API? [closed]
...lement('script'); s.src = src; document.head.appendChild(s); }
window.imdb$foo = function (results) {
/* ... */
};
addScript('https://sg.media-imdb.com/suggests/f/foo.json');
// 2) Using jQuery (JSON-P)
jQuery.ajax({
url: 'https://sg.media-imdb.com/suggests/f/foo.json',
dataType: 'jsonp',...
Cast to int vs floor
...e a new question.
Why do you think they will have the same result?
float foo = (int)(bar / 3.0) //will create an integer then assign it to a float
float foo = fabs(bar / 3.0 ) //will do the absolute value of a float division
bar = 1.0
foo1 = 0;
foo2 = 0.33333...
...
CSS table layout: why does table-row not accept a margin?
...="container">
<div class="row">
<div class="home_1">Foo</div>
<div class="home_2">Foo</div>
<div class="home_3">Foo</div>
<div class="home_4">Foo</div>
</div>
<div class="row">
<div class="hom...
PHP namespaces and “use”
...ace;
is equivalent to:
use My\Full\Namespace as Namespace;
// Namespace\Foo is now shorthand for My\Full\Namespace\Foo
If the use operator is used with a class or interface name, it has the following uses:
// after this, "new DifferentName();" would instantiate a My\Full\Classname
use My\Full\...
How do I unload (reload) a Python module?
...uiltin function (Python 3.4+ only):
from importlib import reload
import foo
while True:
# Do some things.
if is_changed(foo):
foo = reload(foo)
In Python 3, reload was moved to the imp module. In 3.4, imp was deprecated in favor of importlib, and reload was added to the latter....
How to check for an undefined or null variable in JavaScript?
...
A variable that has been declared but not initialized is undefined.
let foo;
if (foo) //evaluates to false because foo === undefined
Undefined properties , like someExistingObj.someUndefProperty. An undefined property doesn't yield an error and simply returns undefined, which, when converted t...
Upgrade python in a virtualenv
... of Python version
Directions:
Let's say your existing project is named foo and is currently running Python 2 (mkproject -p python2 foo), though the commands are the same whether upgrading from 2.x to 3.x, 3.6.0 to 3.6.1, etc. I'm also assuming you're currently inside the activated virtual envir...
typeof for RegExp
...
You can use instanceof operator:
var t = /^foo(bar)?$/i;
alert(t instanceof RegExp);//returns true
In fact, that is almost the same as:
var t = /^foo(bar)?$/i;
alert(t.constructor == RegExp);//returns true
Keep in mind that as RegExp is not a primitive data type,...
jquery variable syntax [duplicate]
... underscore before private variables.
A somewhat popular pattern is:
var foo = 'some string';
var $foo = $('.foo');
That way, you know $foo is a cached jQuery object later on in the code.
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