this - JavaScript: unexpected typeof result -
this - JavaScript: unexpected typeof result -
i have array iterator function:
function applycall(arr, fn) { fn.call(arr[0], 0, arr[0]); }
and code
var arr1 = ['blah']; applycall(arr1, function (i, val) { alert(typeof this); // object why?? alert(typeof val); // string alert(typeof(this === val)) // alerts false, expecting true });
why typeof this
within inline function object
instead of string
?
jsfiddle here
when method called in javascript, internally sets this
calling object: https://developer.mozilla.org/en-us/docs/javascript/reference/global_objects/function/apply
...and primitive values boxed.
by "boxed," mean primitive wrapped in object. note applies first argument apply
/call
. other arguments become function parameters not "boxed."
javascript this typeof
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