Strange javascript syntax -


anybody can me following js syntax? don't understand line starting "( $.inarray( wzdid, this...." mean why line start parentesis? mean?

this complete code:

_activatestep: function( wzdid ) {   if ( condition ) {     var stepindex = this._findnav( wzdid ).index();      for( var = 0; < stepindex; ++i) {        if( condition ) === -1 ) {         return;       }     }     ( $.inarray( wzdid, this._activatedsteps ) === -1 ) && this._activatedsteps.push( wzdid );   } }

thank you

what have here is

a && b

it uses common trick based on short-circuit logical operators : b executed if true.

that's way write

if (a) b;

some people because it's little shorter. it's less readable too.


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