babel-flow-types

1.2.3 verified Sat Apr 25 auth: no javascript maintenance

Provides Flow type definitions for Babel's public API, including types for AST nodes, parsers, transformers, and code generation. Current stable version is 1.2.3. This package is specifically for Flow users who need type coverage when working with Babel's ecosystem, offering types that mirror Babel's internal structures. It is updated infrequently to match Babel's releases. Compared to TypeScript-oriented alternatives like @babel/types, this package is the primary source for Flow consumers relying on Babel.

Common errors

error Cannot resolve 'babel-flow-types'. ↓

cause Package not installed or not in node_modules.

fix

Run 'npm install babel-flow-types' to add it to dependencies.

error TypeError: Cannot read properties of undefined (reading 'body') ↓

cause Trying to use BabelNodeFile as a runtime value instead of a type.

fix

Remove 'type' keyword from import to import the actual value, but note that this package only exports types.

error Flow: Cannot resolve module 'babel-flow-types'. ↓

cause Flow cannot locate the package because it's a flow-typed library or not in flow-typed.

fix

Add '// flow-typed' comment or install flow-typed definitions for babel-flow-types.

Warnings

deprecated This package is in maintenance mode and may not be updated for newer Babel versions. ↓

fix Consider migrating to TypeScript with @babel/types or continue using Flow with caution.

gotcha Flow type definitions may not cover all Babel APIs; some types are missing or incomplete. ↓

fix Check the package's source to see defined types; supplement with custom type definitions as needed.

gotcha Importing types incorrectly (e.g., with default import) will cause Flow errors. ↓

fix Use named type imports as shown in the examples.

Install

npm install babel-flow-types

yarn add babel-flow-types

pnpm add babel-flow-types

Imports

BabelNodeFile
wrong
```
import { BabelNodeFile } from 'babel-flow-types'
```
correct
```
import type { BabelNodeFile } from 'babel-flow-types'
```
This package exports Flow types, so import with 'import type' in Flow or ignore in non-Flow contexts.

BabelNodeIdentifier

wrong

const BabelNodeIdentifier = require('babel-flow-types').BabelNodeIdentifier

correct

import type { BabelNodeIdentifier } from 'babel-flow-types'

CommonJS require is not recommended for type imports; use ESM style.

BabelPluginPass

wrong

import { BabelPluginPass } from '@babel/core'

correct

import type { BabelPluginPass } from 'babel-flow-types'

Incorrect import path; the type is in this package, not @babel/core.

Quickstart

Shows how to import and use a BabelFlow type in a Flow-typed file.

// @flow
import type { BabelNodeFile } from 'babel-flow-types';

function processFile(node: BabelNodeFile) {
  console.log(node.program.body);
}

processFile({ type: 'File', program: { type: 'Program', body: [], directives: [], sourceType: 'module', interpreter: null } });