I wanna know what means the following line in javascript:
$variable1 && $variable2
The line is exactly like a said, without nothing more.
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6http://stackoverflow.com/questions/8720645/operator-in-javascript – Justin Meiners Aug 20 '13 at 18:32
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3$variable1 and $variable2 are 2 bool values and its checking if they both are true – Venkata Krishna Aug 20 '13 at 18:33
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9@Krishna They aren't necessarily boolean values – Mike Park Aug 20 '13 at 18:33
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4Are you sure this isn't PHP? Javascript variables don't normally start with `$` unless they are jQuery objects (that is, NOT boolean) – John Dvorak Aug 20 '13 at 18:34
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2-1 because I suspect you've confused your languages – John Dvorak Aug 20 '13 at 18:36
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@Krishna the values _may_ or _may_ not be an instanceof Boolean of course. – Dimitris Zorbas Aug 20 '13 at 18:38
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@climbage & Dmitris - true – Venkata Krishna Aug 20 '13 at 18:38
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1A lot of down-votes here, but none of the answers on this page or even the supposed "existing question" describe what the && operator really does--which is to return the expression on left if it can be evaluated as `false`, otherwise return the expression on the right. – Peter Aug 20 '13 at 18:45
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1If this really is JS, and the said expressions are not a part of any statement, this does nothing. `&&` operator is executed, but the return value is not used anywhere. Maybe you'd post some more code around this line? – Teemu Aug 20 '13 at 18:47
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Please check this [fiddle](http://jsfiddle.net/5rzs6/), there is a `a && b` on a line alone, though it's a part of a statement. – Teemu Aug 20 '13 at 19:00
3 Answers
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$variable1 and $variable2 are 2 bool values (rightly pointed in comments not always) and its checking if they both are true.
They can also be a jQuery selector's length .. For example:
var $variable1 = someselector.length;
if($variable1)
{
//Some code
}
in the above statement length is an int.. but used to check if the selector exists or not.
Venkata Krishna
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