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typescript/prefer-namespace-keyword Correctness

✅ This rule is turned on by default.

🛠️ An auto-fix is available for this rule.

What it does

This rule reports when the module keyword is used instead of namespace. This rule does not report on the use of TypeScript module declarations to describe external APIs (declare module 'foo' {}).

WARNING

This rule is deprecated and will be removed in a future release.

In a future version of TypeScript and Oxlint, this will be a hard error produced by the parser.

See: https://github.com/microsoft/TypeScript/issues/54500, https://github.com/microsoft/TypeScript/issues/62211 and https://github.com/microsoft/TypeScript/pull/62876.

Why is this bad?

Namespaces are an outdated way to organize TypeScript code. ES2015 module syntax is now preferred (import/export). For projects still using custom modules / namespaces, it's preferred to refer to them as namespaces.

Examples

Examples of incorrect code for this rule:

module Example {}

Examples of correct code for this rule:

namespace Example {}

How to use

To enable this rule using the config file or in the CLI, you can use:

Config (.oxlintrc.json)

{
  "rules": {
    "typescript/prefer-namespace-keyword": "error"
  }
}

CLI

oxlint --deny typescript/prefer-namespace-keyword

References

• Rule Source