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AST Manipulation

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Expert skill for abstract syntax tree design, traversal, transformation, and manipulation patterns

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How to use this skill

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  2. Copy the prompt below and paste it into your agent.
  3. Review the proposed files and risks before you approve installation.
Prompt to paste
I want to install this Agent Skill for this project in Codex.

Source SKILL.md: https://github.com/a5c-ai/babysitter/blob/HEAD/library/specializations/programming-languages/skills/ast-manipulation/SKILL.md

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Copying this prompt does not install or run the skill. Review third-party files before use. Codex skill guide

AST Manipulation Skill

Overview

Expert skill for abstract syntax tree design, traversal, transformation, and manipulation patterns.

Capabilities

  • Design typed AST node hierarchies
  • Implement visitor and transformer patterns
  • Build AST rewriting systems
  • Implement AST diffing and patching
  • Generate AST pretty-printers and formatters
  • Support AST serialization (JSON, binary)
  • Implement pattern matching on AST structures
  • Design span/location tracking systems

Target Processes

  • ast-design.js
  • semantic-analysis.js
  • ir-design.js
  • code-generation-llvm.js
  • lsp-server-implementation.js
  • macro-system-implementation.js

Dependencies

None (core skill)

Usage Guidelines

  1. Node Design: Design immutable AST nodes with clear ownership semantics
  2. Location Tracking: Include source spans on all nodes from the beginning
  3. Visitor Pattern: Implement visitor pattern for extensible traversal
  4. Transformation: Use transformer pattern for AST-to-AST transformations
  5. Serialization: Support both human-readable (JSON) and efficient (binary) serialization

Output Schema

{
  "type": "object",
  "properties": {
    "nodeTypes": {
      "type": "array",
      "items": {
        "type": "object",
        "properties": {
          "name": { "type": "string" },
          "fields": { "type": "array" },
          "parent": { "type": "string" }
        }
      }
    },
    "visitors": {
      "type": "array",
      "items": { "type": "string" }
    },
    "transformers": {
      "type": "array",
      "items": { "type": "string" }
    },
    "generatedFiles": {
      "type": "array",
      "items": { "type": "string" }
    }
  }
}