javascript - why eval can not acess arguments if assigned to local variable -


this question has answer here:

it seems strange me if assign eval variable , call inside function can't access arguments object.

(function() {   ev = eval;    console.log(eval('arguments')); // it's fine   try {     console.log(ev('arguments')); // error here!   } catch (e) {     console.error('ev: ' + e.message);   }       })(1)

interactive example: jsbin

what causes behavior? can reference in spec?


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