{"id":26154,"library":"react-externs","title":"react-externs","description":"Google Closure Compiler externs for Facebook React, providing type definitions to enable advanced Closure Compiler optimizations when compiling React applications. Version 0.13.6 targets React.js 0.13.x. This package is tied to older React versions (0.12–0.14) and is no longer maintained. Alternatives include using official React externs or TypeScript definitions for use with Closure Compiler.","status":"deprecated","version":"0.13.6","language":"javascript","source_language":"en","source_url":"https://github.com/steida/react-externs","tags":["javascript","google","closure","compiler","react","externs"],"install":[{"cmd":"npm install react-externs","lang":"bash","label":"npm"},{"cmd":"yarn add react-externs","lang":"bash","label":"yarn"},{"cmd":"pnpm add react-externs","lang":"bash","label":"pnpm"}],"dependencies":[],"imports":[{"note":"This package provides raw Closure Compiler externs files, not JavaScript modules. Include them via --externs CLI flag.","wrong":"import reactExterns from 'react-externs'; // Not a module","symbol":"reactExterns","correct":"// No import needed; run closure-compiler with --externs node_modules/react-externs/externs.js"},{"note":"Do not require or import the package; it exports nothing.","wrong":"require('react-externs') // Returns unexpected object","symbol":"externs.js file","correct":"// Pass to compiler: closure-compiler --externs node_modules/react-externs/externs.js ..."},{"note":"Reference path is not recognized by Closure Compiler; use --externs.","wrong":"/// <reference path=\"react-externs/externs.js\" /> // Only works in IDEs, not compiler","symbol":"React externs (global)","correct":"// Once included, Closure Compiler knows React API"}],"quickstart":{"code":"// Install:\nnpm install react-externs\n\n# Compile with Closure Compiler (example using google-closure-compiler):\n# npx google-closure-compiler \\\n#   --js input.js \\\n#   --externs node_modules/react-externs/externs.js \\\n#   --compilation_level ADVANCED","lang":"javascript","description":"Shows how to install react-externs and use it with Closure Compiler via --externs flag."},"warnings":[{"fix":"Use official React externs from Closure Compiler repository or upgrade to modern alternatives.","message":"This package targets React 0.13 and is not updated for newer React versions.","severity":"deprecated","affected_versions":">=0.12"},{"fix":"Pass file path directly to Closure Compiler via --externs flag.","message":"Do not import or require the package; it only provides externs files for the compiler.","severity":"gotcha","affected_versions":">=0.12"},{"fix":"Verify coverage or consider using TypeScript .d.ts files converted to externs.","message":"Externs may be incomplete or inaccurate for React features beyond basic components.","severity":"gotcha","affected_versions":">=0.12"}],"env_vars":null,"last_verified":"2026-05-01T00:00:00.000Z","next_check":"2026-07-30T00:00:00.000Z","problems":[{"fix":"Use a newer set of externs (e.g., from Closure Compiler contrib) or suppress warnings.","cause":"Outdated externs not covering new React APIs like createElement signatures.","error":"ERROR - [JSC_TYPE_MISMATCH] actual parameter 1 of React.createElement does not match formal parameter"},{"fix":"Do not require; use --externs flag pointing to externs.js file.","cause":"Package has no main export; it only provides externs files.","error":"require('react-externs') returns {}"}],"ecosystem":"npm","meta_description":null,"install_score":null,"install_tag":null,"quickstart_score":null,"quickstart_tag":null}