javascript - State of a bound parameter in a promise -


i'm curious timing when bind promise.

var = this; function p(){      var promise = new promise(         function (yes, no) {         /* ....  */         /* ....  */         }).then(function (val) {         /* ....  */         /* ....  */         }.bind(this)); }.bind(this)

will condition 

that ===

allways return true, considering scope outside promise async , .then might resolved way later in lifecycle.

in other words, this have same value when first function called, or have value used in .then part?

the value of this determined left of dot in calling method. if you're not calling method of object, this global (window in browser).

in example line var = this sets value of that global variable window (or global). in specific case, equal that. due side effect, if used different object this, in

function (yes, no) {     /* ....  */     /* ....  */ }

this !== that

i'm made little fiddle example http://jsfiddle.net/metaf0x9/


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