What is "==+!" in javascript? -

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does can show me "==+!" meaning in below code:

if(my_var.length==+!0) //do

i try google don't result.

think of this:

if (my_var.length == (+(!0)))

since !0 === true , +true === 1, end sequence of evaluation:

if (my_var.length == (+(!0))) if (my_var.length == (+true)) if (my_var.length == 1)

fyi, can see ordered list of javascript operator precedence when deciding how process operators here.

of relevance here, precendence of ! operator highest, unary + operator , == operator.

see results of !0 , +true here: http://jsfiddle.net/jfriend00/wh840n3q/


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