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JS
JavaScript error

SyntaxError

The JavaScript exception "missing = in const declaration" occurs when a const declaration was not given a value in the same statement (like const RED_FLAG;). You need to provide one (const RED_FLAG = true).

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: Missing initializer in const declaration (V8-based)
As listed by MDN Web Docs
SyntaxError: missing = in const declaration (Firefox)
As listed by MDN Web Docs
SyntaxError: Unexpected token ';'. const declared variable 'x' must have an initializer. (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 2026-09-25T01:48:37.274Z.