Menhir Parser Generator
Menhir is a powerful parser generator for the OCaml programming language. It takes grammar definitions written in the Menhir syntax (typically in `.mly` files) and generates efficient OCaml code for parsing input according to those grammars.
OCaml Parser Generation with Menhir
This section provides a comprehensive guide to using Menhir for generating OCaml parsers. We cover basic usage, advanced options for debugging and customization, and best practices for integrating Menhir into your OCaml projects.
Menhir Command-Line Usage Examples
Below are common command-line invocations for the menhir
tool, illustrating its various functionalities:
# menhir
# Parser generator for OCaml.
# Basic usage to generate a parser from a grammar file
menhir grammar.mly
# Generate and display the parser's automaton
menhir --dump grammar.mly
# Produce detailed explanation of conflicts (useful for debugging grammar conflicts)
menhir --explain grammar.mly
# Generate the parser with error messages in a separate file
menhir --error-recovery grammar.mly
# Specify a start symbol for the parser
menhir --entry <entry_point> grammar.mly
# Generate a parser that can be selectively compiled with manual intervention
menhir --table grammar.mly
# Use an existing .cmly file to check compatibility or produce additional outputs
menhir --interpret grammar.cmly
# Specify standard library directory for use with OCaml's standard library
menhir --stdlib <directory> grammar.mly
# Create a parser that enables incremental parsing
menhir --incremental grammar.mly
# Produce a Makefile-compatible dependency listing
menhir --depend grammar.mly
Understanding OCaml Parser Conflicts
When defining grammars, conflicts can arise. Menhir provides tools to help identify and resolve these issues. Understanding parsing techniques and grammar design is crucial for writing unambiguous grammars.
Integrating Menhir into OCaml Projects
Menhir parsers can be seamlessly integrated into larger OCaml applications. This involves generating the parser code and then using the generated OCaml modules within your project. Tools like Dune can manage the build process effectively.