esmangle2

library1.0.11jsnpmunverified

esmangle is a ECMAScript code mangler and minifier that operates on Mozilla Parser API AST. It is part of the estools ecosystem (esprima, escodegen) and is designed to work with AST-based transformations for JavaScript minification. Version 1.0.11 is the latest stable release, but the project appears to be unmaintained (last release in 2014). Key differentiators: supports both Node.js and browser environments, provides optimize and mangle passes, and integrates with esprima for parsing and escodegen for code generation.

devops

npm install esmangle2

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INSTALL

IMPORT

SIG · ESMANGLE2

esmangle2

devopsjavascriptv1.0.11

harness data pending

Install & Compatibility

Where this runs

No compatibility data collected yet for this library.

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

esmangle

✓ import esmangle from 'esmangle'

✗ const esmangle = require('esmangle')

As an old package, it uses CommonJS exports; default import works in modern bundlers, but require() is also valid.

mangle

✓ import { mangle } from 'esmangle'

✗ const { mangle } = require('esmangle')

mangle is a named export; works in both ESM and CJS environments.

optimize

✓ import { optimize } from 'esmangle'

✗ import optimize from 'esmangle'

optimize is a named export, not a default export. Using default import will give undefined.

This demonstrates the full pipeline: parsing code with esprima, optimizing and mangling with esmangle, then generating minified code with escodegen.

import * as esprima from 'esprima'; import * as escodegen from 'escodegen'; import { mangle, optimize } from 'esmangle'; const code = 'function square(n) { return n * n; }'; const ast = esprima.parseScript(code); const optimized = optimize(ast, null); const mangled = mangle(optimized); const result = escodegen.generate(mangled, { format: { renumber: true, hexadecimal: true, escapeless: true, compact: true, semicolons: false, parentheses: false } }); console.log(result);

Debug

Known issues

deprecatedesmangle is unmaintained and no longer updated. Use modern minifiers like terser or esbuild instead.

fix

Migrate to terser or esbuild for active development and ES6+ support.

affects: all

gotchaesmangle only works with ES5 code. It does not support ES6+ syntax (e.g., arrow functions, classes). Parsing modern code with esprima will fail or produce incorrect results.

fix

Transpile modern code to ES5 before using esmangle, or switch to a minifier that supports ES6+.

affects: <=1.0.11

gotchaThe CLI command 'esmangle' may not be globally available and requires local install.

fix

Run via npx or install locally: npx esmangle file.js

affects: all

gotchaThe browser build is only available for old browsers (no module support). Download the pre-built file from the GitHub pages.

fix

Use a CDN link or include script tag. Note that it pollutes the global scope.

affects: all

Errors

Common errors & fixes

Cannot find module 'esmangle'

The package is not installed or is missing from node_modules.

fix

Run 'npm install esmangle' or add it to package.json.

esprima.parse is not a function

Using esprima's parseScript incorrectly; esprima v4+ uses parseScript instead of parse.

fix

Use 'esprima.parseScript(code)' for modules or 'esprima.parseScript(code, { jsx: true })' if using JSX. For ES5, 'esprima.parse(code)' works but is deprecated.

esmangle.mangle is not a function

The imported object may be incorrect due to CommonJS vs ESM mismatch.

fix

Ensure you use the correct named import: 'const { mangle } = require("esmangle");' or 'import { mangle } from "esmangle";'

Upgrade

Version history

1.0.11latest on npm

Audit

Dependencies

No dependency data recorded yet.

Agent activity

2 hits · last 30 days

node

Resources

githubssh://git@github.com/estools/esmangle ↗

packageesmangle2 ↗

homepagehttp://github.com/estools/esmangle.html ↗