Registry / serialization / messageformat-parser

messageformat-parser

library4.1.3jsnpmunverified

A PEG.js-based parser for ICU MessageFormat strings, used by the messageformat library to parse ICU message patterns into an AST. Current stable version is 4.1.3, with a release cadence aligned with the messageformat monorepo. Key differentiators: implements the ICUMessageFormat specification, supports plural, select, and complex patterns, and is the heritage parser before the shift to MF2 in messageformat v4. It is lightweight and focused solely on parsing.

serialization

npm install messageformat-parser

github ↗package ↗homepage ↗

INSTALL

IMPORT

SIG · MESSAGEFORMAT-PARS

messageformat-parser

serializationjavascriptv4.1.3

Install

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Import

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Disk

—

Pass rate

0/ 6

Env Coverage0 / 6

glibc

18–22

musl

18–22

Install & Compatibility

Where this runs

tested against v? · npm install

Install × environment matrix

Each cell = how many times install + import succeeded across repeated harness runs. Partial = flaky.
glibc = Debian/Ubuntu slim · musl = Alpine Linux

musl

node 18–226 runs

build_error

glibc

node 18–226 runs

build_error

Code

Verified usage

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

parse

✓ import { parse } from 'messageformat-parser'

✗ import parse from 'messageformat-parser'

The parser is a named export, not a default export. Use named import.

PegParser

✓ import { PegParser } from 'messageformat-parser'

PegParser is an alternative entry point for custom usage. Available since v4.

Illustrates parsing an ICU MessageFormat string with plural arguments using messageformat-parser.

import { parse } from 'messageformat-parser'; const ast = parse('You have {count, plural, one {# item} other {# items}}.'); console.log(JSON.stringify(ast, null, 2)); // Output shows parsed AST with type, plural, etc.

Debug

Known issues

breakingmessageformat v4 switched to a new MF2 parser; this package is for legacy ICUMessageFormat only.

fix

Use messageformat (the full package) for MF2 support, or continue using messageformat-parser for ICU MessageFormat.

affects: >=4.0.0

gotchaThe parser does not implement string interpolation or variable substitution; it only returns an AST.

fix

Use messageformat or another library to format the AST into a string.

affects: all

deprecatedparse() now returns a simpler AST in v4; check types for migration from v3.

fix

Update your code to use the new AST shape: 'type' property is string, not a number.

affects: >=4.0.0

Errors

Common errors & fixes

Cannot find module 'messageformat-parser'

Package not installed or version mismatch.

fix

Run 'npm install messageformat-parser' and ensure it's in your dependencies.

SyntaxError: Expected "{" ...

Invalid ICU message syntax, e.g., unescaped quotes or mismatched braces.

fix

Check message format specification and escape single quotes with ''.

TypeError: parse is not a function

Importing default instead of named export.

fix

Use import { parse } from 'messageformat-parser' instead of importing default.

Upgrade

Version history

4.1.3latest on npm

Audit

Dependencies

No dependency data recorded yet.

Agent activity

4 hits · last 30 days

node

Resources

githubhttps://github.com/messageformat/messageformat ↗

packagehttps://www.npmjs.com/package/messageformat-parser ↗

homepagehttps://messageformat.github.io/ ↗