Parser Generator

SkillDev tools

Expert skill for parser generation and implementation using LL, LR, LALR, PEG, and Pratt parsing techniques

Instructions available. Your AI can read the instructions. Execution depends on the setup they require.

Account requirements not reviewed. Check the skill instructions before use; ahel provides instructions and does not run this skill.

Add ahel to your AI once: Claude, ChatGPT, Cursor, Claude Code or Codex. Then ask it to use this.

Then ask your AI: use the Parser Generator skill

What this skill tells your AI

The instructions your AI receives, as published by a5c-ai/babysitter in library/specializations/programming-languages/skills/parser-generator/SKILL.md and read by ahel’s review.

Overview

Expert skill for parser generation and implementation using LL, LR, LALR, PEG, and Pratt parsing techniques.

Capabilities

Generate parsers from grammar specifications (ANTLR, Bison, tree-sitter)
Implement recursive descent parsers with predictive parsing
Implement Pratt parsers for expression handling
Generate LALR/GLR parse tables
Implement PEG parsers with packrat memoization
Handle grammar conflicts (shift-reduce, reduce-reduce)
Generate concrete syntax trees (CST) and AST transformations
Implement operator precedence parsing

Target Processes

parser-development.js
language-grammar-design.js
ast-design.js
lsp-server-implementation.js

Dependencies

ANTLR4
tree-sitter
Bison/Yacc

Usage Guidelines

Grammar Analysis: Analyze grammar class requirements (LL(k), LALR, etc.) before selecting parser type
Conflict Resolution: Document and resolve all shift-reduce/reduce-reduce conflicts explicitly
Error Recovery: Implement synchronization points for robust error recovery
AST Construction: Design AST node types before implementing production actions
Expression Parsing: Use Pratt parsing for complex expression precedence handling

Output Schema

{
  "type": "object",
  "properties": {
    "parserType": {
      "type": "string",
      "enum": ["recursive-descent", "pratt", "lalr", "glr", "peg", "ll"]
    },
    "grammarClass": { "type": "string" },
    "conflicts": {
      "type": "array",
      "items": {
        "type": "object",
        "properties": {
          "type": { "type": "string" },
          "resolution": { "type": "string" }
        }
      }
    },
    "generatedFiles": {
      "type": "array",
      "items": { "type": "string" }
    }
  }
}

Signals

GitHub stars: 2k
Forks: 112
Last commit: Sep 2026

Advanced

Item type: skill
Key: parser-generator
Source: github.com/a5c-ai/babysitter

github.com/a5c-ai/babysitter