Are Javascript Object Properties assigned in order? -


say have object assigns properties based off return value of function:

var = 0;  var f = function() { return ++i; }  var foo = {             a:f(),             b:f(),             c:f()           };

is guaranteed foo.a 1, foo.b 2, , foo.c 3? know js doesn't guarantee order when iterate on object, assignment?

is specified in js specification somewhere? i'm asking educational reasons.

thanks.

standard ecma-262 (5.1) - section 11.1.5 - object initialiser

the production propertynameandvaluelist : propertynameandvaluelist , propertyassignment evaluated follows:

1. let obj result of evaluating propertynameandvaluelist. 2. let propid result of evaluating propertyassignment. ... 5. call [[defineownproperty]] internal method of obj arguments propid.name, propid.descriptor, , false. 6. return obj.

so yes, order enforced standard.


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