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JS
JavaScript error

SyntaxError

The JavaScript strict mode-only exception "'arguments' can't be defined or assigned to in strict mode code" or "'eval' can't be defined or assigned to in strict mode code" occurs when attempting to create a called arguments or eval, or assign to such a name.

Reference entryJavaScriptFetched
This is a reference entry from MDN Web Docs. A full explanation with fixes has not been written yet.

The error messages

SyntaxError: Unexpected eval or arguments in strict mode (V8-based)
As listed by MDN Web Docs
SyntaxError: 'arguments' can't be defined or assigned to in strict mode code (Firefox)
As listed by MDN Web Docs
SyntaxError: Cannot modify 'arguments' in strict mode. (Safari)
As listed by MDN Web Docs
SyntaxError: Cannot destructure to a parameter name 'arguments' in strict mode. (Safari)
As listed by MDN Web Docs
SyntaxError: Cannot declare a variable named arguments in strict mode. (Safari)
As listed by MDN Web Docs
SyntaxError: Cannot declare a catch variable named 'arguments' in strict mode. (Safari)
As listed by MDN Web Docs
SyntaxError: 'arguments' is not a valid function name in strict mode. (Safari)
As listed by MDN Web Docs

Details

Category
SyntaxError
Severity
error
Runtime
both

Related errors

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Source: MDN Web Docs. Data fetched 2026-09-25T01:48:37.273Z.