{"id":18984,"library":"babel-core","title":"Babel Core","description":"Babel compiler core version 6.26.3. This is an outdated version of Babel (pre-7.x). The current stable releases are v7.29.2 (2026-03-16) and v8.0.0-rc.3 (2026-03-16). babel-core v6 is no longer maintained and should not be used for new projects. Key differentiator vs v7/v8: v6 uses the `babel-core` package while v7+ uses `@babel/core`. It provides core transformation API including `transform`, `transformFile`, `transformFileSync`, and `transformFromAst` methods. Compatible with Node.js and browsers via bundlers. Does not include presets/plugins; those are separate packages.","status":"deprecated","version":"6.26.3","language":"javascript","source_language":"en","source_url":"https://github.com/babel/babel/tree/master/packages/babel-core","tags":["javascript","6to5","babel","classes","const","es6","harmony","let","modules"],"install":[{"cmd":"npm install babel-core","lang":"bash","label":"npm"},{"cmd":"yarn add babel-core","lang":"bash","label":"yarn"},{"cmd":"pnpm add babel-core","lang":"bash","label":"pnpm"}],"dependencies":[],"imports":[{"note":"Default import provides the main API object. CommonJS require works but ESM is preferred for bundlers.","wrong":"const babel = require('babel-core')","symbol":"default","correct":"import babel from 'babel-core'"},{"note":"transform is a named export. Named export is available since v6.","wrong":"import transform from 'babel-core'","symbol":"transform","correct":"import { transform } from 'babel-core'"},{"note":"Asynchronous transform of a file. Named export.","symbol":"transformFile","correct":"import { transformFile } from 'babel-core'"},{"note":"Synchronous version of transformFile.","symbol":"transformFileSync","correct":"import { transformFileSync } from 'babel-core'"},{"note":"Transform from an AST object.","symbol":"transformFromAst","correct":"import { transformFromAst } from 'babel-core'"}],"quickstart":{"code":"import { transform } from 'babel-core';\n\nconst code = 'const x = (a, b) => a + b;';\nconst result = transform(code, {\n  presets: ['env'] // requires @babel/preset-env or babel-preset-env\n});\nconsole.log(result.code);\n// Output: \"var x = function x(a, b) { return a + b; };\"","lang":"typescript","description":"Transforms ES6 arrow function to ES5 using babel-core transform API with env preset."},"warnings":[{"fix":"Install @babel/core: npm install --save-dev @babel/core and update imports to use '@babel/core'.","message":"babel-core v6 is deprecated. Use @babel/core v7+ instead.","severity":"deprecated","affected_versions":">=6.0.0 <7.0.0"},{"fix":"Install presets: npm install --save-dev babel-preset-env and add 'presets: [\"env\"]' to options.","message":"babel-core v6 does not include any presets. You must install presets separately (e.g., babel-preset-env) to transpile ES6+ code.","severity":"gotcha","affected_versions":">=6.0.0 <7.0.0"},{"fix":"Set options.babelrc = false to ignore .babelrc files.","message":"User-local configuration files (.babelrc) are automatically loaded if babelrc option is not set to false. This may cause unexpected behavior.","severity":"gotcha","affected_versions":">=6.0.0 <7.0.0"},{"fix":"Review Babel v7 migration guide for option changes.","message":"In babel-core v6, default options differ from v7 (e.g., 'ast' defaults to true). Be aware when migrating.","severity":"breaking","affected_versions":">=6.0.0 <7.0.0"}],"env_vars":null,"last_verified":"2026-04-25T00:00:00.000Z","next_check":"2026-07-24T00:00:00.000Z","problems":[{"fix":"Install babel-core v6: npm install --save-dev babel-core@6.26.3 or migrate to v7: npm install --save-dev @babel/core.","cause":"babel-core not installed or moved to @babel/core in v7.","error":"Error: Cannot find module 'babel-core'"},{"fix":"Use import { transform } from 'babel-core' or const transform = require('babel-core').transform.","cause":"Using default import incorrectly; transform is a named export.","error":"TypeError: babel.transform is not a function"},{"fix":"Ensure all babel packages are of the same major version. For v6, use packages like babel-preset-env; for v7, use @babel/preset-env.","cause":"Mixing babel-core v6 with plugins/presets designed for v7.","error":"Error: Requires Babel \"7.0.0-0\" but was loaded with \"6.26.3\""}],"ecosystem":"npm","meta_description":null,"install_score":null,"install_tag":null,"quickstart_score":null,"quickstart_tag":null}