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require-verbatim-module-syntax

Require "verbatimModuleSyntax": true in compilerOptions for projects targeting ESM, to ensure that import type and export type are used correctly and that type-only imports are never emitted as value imports.

Targeted pattern scopeโ€‹

The compilerOptions.verbatimModuleSyntax and compilerOptions.module fields in any tsconfig*.json file.

What this rule reportsโ€‹

This rule reports when module is set to "ESNext", "NodeNext", or "Node16" and verbatimModuleSyntax is absent or set to false.

Why this rule existsโ€‹

Without verbatimModuleSyntax, TypeScript's older importsNotUsedAsValues and preserveValueImports flags controlled how type-only imports were handled. These two flags had confusing interaction semantics and were deprecated in TypeScript 5.0.

verbatimModuleSyntax replaces both with a single, clear rule: every import and export statement is emitted exactly as written. An import without type is treated as a value import; an import with type (or an import type โ€ฆ) is erased at emit time. This means:

  • Type-only imports that are not marked import type will cause a compile error, preventing accidental value imports that resolve to undefined at runtime.
  • Bundlers and runtimes see exactly the imports the developer wrote, with no hidden transformations.
  • IDE tooling can reliably determine which imports are type-only and apply automatic import type insertion.

The auto-fixer adds "verbatimModuleSyntax": true to compilerOptions.

โŒ Incorrectโ€‹

{
    "compilerOptions": {
        "module": "NodeNext",
        "moduleResolution": "NodeNext"
    }
}

Type-only imports may be emitted as value imports, silently resolving to undefined at runtime.

โœ… Correctโ€‹

{
    "compilerOptions": {
        "module": "NodeNext",
        "moduleResolution": "NodeNext",
        "verbatimModuleSyntax": true
    }
}

When not to use itโ€‹

Disable this rule for CommonJS-only projects ("module": "CommonJS") where esModuleInterop is used instead, or for legacy projects that have not yet migrated from importsNotUsedAsValues.

Package documentationโ€‹

Rule catalog ID: R025

Further readingโ€‹