Javascript closure with new and this -

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i playing new, this, , javascript , ran across , have no idea why javascript behaves way. wrapping head around great.

lets have function:

 function x() {     this.q = function() {         console.log(this);     };        console.log(this); }

this works expect:

 var x = new x(); => x {q: function}  x.q(); => x {q: function}

but not act expect:

 function func(f) {     f(); }  var x = new x(); => x {q: function}  func(x.q); => window {top: window, window: window, location: location, external: object, chrome: object…} // expected return "x {q: function}"  // works... func(function() {x.q()}); => x {q: function}

i seem misunderstanding javascript because way behaves in case nothing how expect to.

because context (this) of function set how call it in javascript not where declared other languages.

so when call function f() there no context defaults window when call x.q() context x instance.

if called function like:

obj.something.deep.property.func();

in case context (this) of function whatever property is.

(note: strict mode if no context determined this undefined, not window)


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