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ReferenceError: deprecated caller or arguments usage

The JavaScript strict mode-only exception "deprecated caller or arguments usage" occurs when the deprecated Function.prototype.caller or Function.prototype.arguments properties are used.

Message

TypeError: 'caller', 'callee', and 'arguments' properties may not be accessed on strict mode functions or the arguments objects for calls to them (V8-based & Firefox)
TypeError: 'arguments', 'callee', and 'caller' cannot be accessed in this context. (Safari)

Error type

TypeError in strict mode only.

What went wrong?

In strict mode, the Function.prototype.caller or Function.prototype.arguments properties are used and shouldn't be. They are deprecated, because they leak the function caller, are non-standard, hard to optimize and potentially a performance-harmful feature.

Examples

Deprecated function.caller or arguments.callee

Function.prototype.caller and arguments.callee are deprecated (see the reference articles for more information).

"use strict";

function myFunc() {
  if (myFunc.caller === null) {
    return "The function was called from the top!";
  } else {
    return `This function's caller was ${myFunc.caller}`;
  }
}

myFunc();
// TypeError: 'caller', 'callee', and 'arguments' properties may not be accessed on strict mode functions or the arguments objects for calls to them

Function.prototype.arguments

Function.prototype.arguments is deprecated (see the reference article for more information).

"use strict";

function f(n) {
  g(n - 1);
}

function g(n) {
  console.log(`before: ${g.arguments[0]}`);
  if (n > 0) {
    f(n);
  }
  console.log(`after: ${g.arguments[0]}`);
}

f(2);

console.log(`returned: ${g.arguments}`);
// TypeError: 'caller', 'callee', and 'arguments' properties may not be accessed on strict mode functions or the arguments objects for calls to them