@atlisp/parser

S-expression parser for AutoLISP — AST types, tree walker, visitor pattern.

Install

npm install @atlisp/parser

Usage

import { parseAst, astWalk, astIsList, astIsSymbol, AstVisitor } from '@atlisp/parser'

const ast = parseAst('(+ 1 2 (* 3 4))')

// Walk all nodes
for (const node of astWalk(ast)) {
  console.log(node.type, node.pos)
}

// Check node types
if (astIsList(ast)) { /* ... */ }
if (astIsSymbol(node, 'defun')) { /* ... */ }

// Visitor pattern
const visitor = new AstVisitor()
visitor.on('defun', (node) => {
  console.log('Found defun:', node.children?.[1]?.name)
})
visitor.run(ast)

API

| Function | Description | |----------|-------------| | parseAst(content) | Parse entire input into an AST root node | | parseContent(content) | Parse input, return top-level forms as array | | astChildren(node) | Get children of a node | | astIsSymbol(node, name?) | Type guard for symbol nodes | | astIsList(node, head?) | Type guard for list nodes | | astWalk(node) | Generator yielding all descendants depth-first | | astFindAll(node, predicate) | Find all nodes matching a predicate | | astFindListWithHead(node, headName) | Find lists with a given head symbol | | AstVisitor | Class with on(name, handler) / run(root) |

Build

npm run build    # tsc
npm run typecheck # tsc --noEmit