local variables - Does javascript implement lexical scoping? -

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this question has answer here:

why return 2 instead of 1? seems second "var" silently ignored.

function foo() {   var local = 1;   {     var local = 2;   }   return local; } foo() /* 2 */

in javascript there function level scope , global scope. cannot create block scope , adds no special meaning , not create scope.

and how code ends up

function foo() {   var local = 1;   local = 2;   return local; } foo();

in es6 can create block level scopes of let. es6 not supported yet. more on here


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