@giduru/codemirror-lang-hledger

hledger journal format language support for CodeMirror 6.

Features

• Syntax highlighting for transactions, postings, amounts, account names, dates, comments, directives, and more
• Code folding for transactions and multi-line directives
• Auto-indentation for postings under transaction headers
• Autocompletion for directive keywords and common account prefixes
• Toggle line comments with ;

Installation

npm install @giduru/codemirror-lang-hledger

Usage

import {EditorView, basicSetup} from "codemirror"
import {hledger} from "@giduru/codemirror-lang-hledger"

new EditorView({
  extensions: [basicSetup, hledger()],
  parent: document.body
})

If you only need the language without autocompletion and folding:

import {hledgerLanguage} from "@giduru/codemirror-lang-hledger"

Supported syntax

• Transactions: dates (including DATE=DATE2), status markers (*/!), codes, payee|description text, same-line ; comments, indented transaction comments
• Postings: account names (with single-space support and journal-style semicolons), amounts, commodity symbols, cost (@/@@), balance assertions (=/==/=*/==*), lot prices ({...} / {{...}}), lot dates ([DATE]), inline comments
• Virtual postings: (account) and [account] syntax
• Periodic transactions: ~ monthly, ~ weekly, etc.
• Auto posting rules: = query
• Directives: account, commodity, payee, tag, include, alias, end aliases, decimal-mark, apply account, apply year, apply tag, apply fixed, end ..., assert, capture, check, define, expr, value, eval, P (market price), D (default commodity), Y/year, C, A/bucket, N, and command-line --flag directives
• Directive details: same-line ; comments on account/commodity/include/payee/tag directives, commodity format subdirectives, and legacy ! / @ directive prefixes
• Price directives: P directives expose structured PriceDate, PriceCommodity, and PriceAmount nodes instead of flattening the body into one generic argument string
• Comments: line comments (;, #, *), indented top-level file comments, and block comments (comment...end comment)
• Date formats: YYYY-MM-DD, YYYY/MM/DD, YYYY.MM.DD

Notes

• The grammar models journal syntax, not all of hledger's semantic validation rules.
• Transaction codes are still part of TxnDescription, not a separate AST node.
• Tags and posting dates embedded inside comment text are still extracted by a higher-level parser layer, not by the Lezer grammar itself.
• Multi-line python directives are not modeled yet.