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arguments.length

Baseline Widely available

This feature is well established and works across many devices and browser versions. Its been available across browsers since 2015 ..

arguments.length , .

In this article

arguments.length

arguments.length . count (. Function.length).

arguments.length

, 2 .

js
function adder(base /*, n2, ... */) {
  base = Number(base);
  for (var i = 1; i < arguments.length; i++) {
    base += Number(arguments[i]);
  }
  return base;
}

Specification
ECMAScript 2027 LanguageSpecification
# sec-arguments-exotic-objects

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