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tsx.require()

Native require() function enhanced with TypeScript & ESM support.

Use this function for importing TypeScript files in CommonJS mode without adding TypeScript support to the entire runtime.

Note, the current file path must be passed in as the second argument to resolve the import context.

Caveats

  • import() calls in the loaded files are not enhanced.
  • Because it compiles ESM syntax to run in CommonJS mode, top-level await is not supported

Usage

CommonJS

js
const tsx = require('tsx/cjs/api')

const tsLoaded = tsx.require('./file.ts', __filename)
const tsFilepath = tsx.require.resolve('./file.ts', __filename)

ESM

js
import { require } from 'tsx/cjs/api'

const tsLoaded = require('./file.ts', import.meta.url)
const tsFilepath = require.resolve('./file.ts', import.meta.url)

Tracking loaded files

Because the CommonJS API tracks loaded modules in require.cache, you can use it to identify loaded files for dependency tracking. This can be useful when implementing a watcher.

js
const resolvedPath = tsx.require.resolve('./file', import.meta.url)

const collectDependencies = module => [
    module.filename,
    ...module.children.flatMap(collectDependencies)
]

console.log(collectDependencies(tsx.require.cache[resolvedPath]))
// ['/file.ts', '/foo.ts', '/bar.ts']