A modified version of yacc that supports automatic backtracking and semantic disambiguation to parse ambiguous grammars. It also has syntactic sugar for inherited attributes.

Approaches lexical analysis by basing the scanner strictly on the object-oriented paradigm. It can be extended without access to the source code in that symbol recognizers can be derived by inheritance and an executing scanner can be reconfigured for different contexts.

A general-purpose parser generator that converts a grammar description for an LALR context-free grammar into a C program to parse that grammar. [Open source, GPL]

A simple to use translator generator.

A tool for generating an efficient recursive descent parser from an ELL(1) grammar. The grammar may be ambiguous or more general than ELL(1): there are both static and dynamic facilities to resolve the ambiguities.

object-oriented grammar definition language and integrated suite of visual tools that assist in building, testing and debugging parsers.

A parser generator for Haskell.

Very simple LALR(1) open-source parser generator. Outputs C, claims to produce faster parsers than yacc/bison.

a compiler generator for Turbo Pascal and compatibles. The package contains two programs, TP Lex and Yacc, which are approximately compatible with the UNIX utilities Lex and Yacc, but are written in and produce code for the Turbo Pascal programming language. The present version works with all recent flavours of Turbo/Borland Pascal, including Delphi and Free Pascal Compiler, a GPL'ed Turbo Pascal-compatible compiler which currently runs on DOS and Linux.

Tutorial in Lex and Yacc, tools that simplify compiler construction.

Generates fast tree parsers for cost-augmented tree grammars. A variant of iburg is used in the code generators for lcc.

Object-oriented rewrite of Lex and Yacc for C++, with automatic AST class generation, grammar inheritance, minimal state ELR(1) and technology. (Commercial package)

The primary source of maintenance releases for the PCCTS compiler construction tool set. PCCTS is an LL(k) recursive descent parser generator with semantic predicates and backtracking. It was developed by T.J. Parr.

a scanner+LL(k = 1..Inf) parser generator for C++. Allows easy top-down description of grammars in an intuitive and extensible manner. Good generated code speed (as comared to GNU Flex/Bison). [Open source, GPL]

The version of BtYacc on siber.com suffers from a few minor, but annoying bugs. This is a page with patches.

All about Lex, Yacc, Flex, and Bison: Overview, Online Documentation, Papers, Tools, Pointers

A Flex like scanner code generator, but it generates C++ scanner classes that are re-entrant and compatible with the newer standard of C++/STL. Multiple scanner classes and instances can co-exist in a program without tweaking of macros.

An object oriented recursive descent parser generator framework implemented using template meta-programming techniques. Expression templates allow to approximate the syntax of Extended Backus Normal Form (EBNF) completely in C++.

Closed-source, but free LALR(2) parser generator, accepts yacc input with some extensions.

Almost as fast as Bison (for deterministic portions of input), but can parse any context-free grammar. [Open source, BSD]

an infinite-lookahead parser generator for context dependent grammars which generates ANSI C code. Specification scripts are in very extended BNF with inherited and synthetic attributes allowed. Scripts can be compiled in separate modules and later linked together, and meta-production rules are allowed. Converter for yacc scripts is available.

Provides a powerful grammar notation, special features for maintenance of highly configurable parsers, visual parsing and unique interactive debugging tools, supporting thread-safe parsers. The program produces C/C++ parsers for use on any platform and runs under Win9x/NT. A free trial copy is available.

The tool allows visual design of lexers and parsers for use in C++, Java, Delphi and Visual Basic applications under UNIX, Linux and Windows/NT. New to version 4.0 is support for XML, XPath, XSLT, XPointer, XQL, DTD and Namespaces.

A scanner and lalr(1) parser generator. It has features like automatic derivation of depth grammar, production of the abstract syntax tree including its C interface and preserves full source information to faciliate source-source translation.

This compiler frontend generation system based on an ECLR-attributed grammar is open source, written in C and may be regarded as an extension of Yacc/Bison.

An object-oriented parser generator implemented in Java.

A free parser generator. Unlike common compiler-compilers, the GOLD Parser does not require you to embed your grammar directly into your source code. Instead, the Builder analyzes the grammar description and saves the parse tables to a separate file. This file can be subsequently loaded by the actual parser engine and used. Currently the GOLD Parser Engine is available in Java, .NET and ActiveX. [Open Source]

Yet another Yacc, which accept yacc grammar nad produce C++ template-based reentrant code. [Open Source, BSD license]

A version of yacc for Java rather than C. Documentation in German.

Flex/Bison ports to Win32, includes MAN pages, and email list for peer to peer support.

A port of the Java-Bison/Flex software developed by the Serl project at the University of Colorado, Boulder. Parsers and lexers will be able to use C# actions. The open source .NET project Mono has requested the port, and here it is. [Open source, BSD License]

Coco/R combines the functionality of the well-known UNIX tools lex and yacc, to form an extremely easy to use compiler generator that generates recursive descent parsers, their associated scanners, and (in some versions) a driver program, from attributed grammars (written using EBNF syntax with attributes and semantic actions) which conform to the restrictions imposed by LL(1) parsing (rather than LALR parsing, as allowed by yacc).

A fast lexical analyser generator. It is a tool for generating programs that perform pattern-matching on text. There are many applications for Flex, including writing compilers in conjunction with GNU Bison. [Open source, GPL]

Pattern matching in syntax analysis as influenced by SNOBOL4. The library distributed under the GNU Library General Public License provides for recursive patterns, various iterators and user-defined patterns along with bindings for Ada, K and R C/ANSI C/C++.

A runtime parser generator library. It generates parsers from BNF-like language grammars. Parsing scripting languages and communication protocol messages are typical use cases. [Public domain]

re2c is a tool for writing fast and flexible lexers. A re2c generated scanner is usually 2-3 times faster than a flex based scanner, and its input model is much more flexible.

Produces compact and efficient table-driven LL(k) parsers in C, C++, C#, and Java. Features include automated grammar transformations, clean EBNF syntax, backtracking, new LL(k) algorithms, and an uncomplicated API.

Port of lex and yacc to Delphi 3. Base at port to Turbo Pascal.

A parsergenerator, a simple c++ interpreter and an interactive debugger combined to a visual development environment, which analyzes, evaluates, converts texts immediately.

A compiler compiler that uses the Extended Affix Grammar (EAG) formalism which describes both the context free and context sensitive syntax of language. The compiler generates either a recognizer or a transducer or a translator or a syntax-directed editor for a described language.

LLOOP generates C++ LL(1) parsers from EBNF grammars and allows a tight integration with object-oriented applications, based on a symbol/class mapping. The generated code can also perform the reverse operation (expanding), whereby the original input can be re-constituted or modified.

An object oriented recursive descent parser generator framework implemented using C++ operator overloading techniques. It is inspired by Spirit, but use only few template classes thus allowing more flexibility and fastest compilation time. [Open source, LGPL]

A powerful tool for the automatic generation of Visual Programming Environments. Its new reworked version of Visual Language Compiler-Compiler (VLCC).

Various GNU tools and software for Win32 including ports of bison, byacc, and flex

Compiles FSMs from regular languages into executable C, C++, Objective-C or D code. The GPL'ed software can be used to create a parser for any language that is regular. Examples include parsing Unix mailbox files and general lexing tasks.

GUI based call tree, source code analyzers for any C compiler and also generates HTML reports.

A parser generator which compiles attributed LL(1) grammars decorated with C semantic actions into recursive descent compilers.

TPG is a parser generator for Python. Given a simple attributed grammar, TPG produces a Python Recursive Descent Parser. It is simple and useful for small parsers for everyday use.

An interpreting parser, meaning that it accepts as input a grammar and a source file to be parsed according to that grammar, producing an abstract program tree. Very compact implementation.

A small, flexible parsing engine with practically unlimited backtracking capability. [Commercial]

Interprets parse tables generated from an SDF2 syntax definition. Scannerless means that no scanner is used to tokenize the input stream; the parse table contains enough information for both the lexical and the context-free syntax. [Open source, LGPL]

An LR(1) parser by Intralogic for Backus-Naur form and generating parse tables DLL's in .NET assembly.

Grammatica is a free LL(k) parser generator (compiler compiler) for C# and Java. Support for automatic error recovery, and instant parsing is available.

The combined lexical analyzer and parser generator, which converts a description for a context-free LALR grammar into source file to parse the grammar. [Open source, GPL]

The Meta-S Type-0 adaptive context-sensitive parsing calculus and the Grammar Forge IDE for developing and testing Meta-S grammars.

Kelbt generates backtracking LALR(1) parsers. Whereas standard LALR(1) parser generators emit an error upon encountering a conflict in the parse tables, Kelbt forges onward, generating parsers which handle conflicts by backtracking at runtime. As Kelbt is able to generate a parser for any context-free grammar, it therefore implements a generalized parsing method.

JS/CC is a LALR(1) parser and lexer generator for JavaScript/ECMAScript which is entirely written in JavaScript.

A retargeting of bison-1 and flex 2.3 to C++ capable of generating classes. As with Bison and Flex these two tools are independent but designed for mutual compatibility. Examples are provided to help in getting started.

A lexer and parser generator of LALR parsers and DFA lexers from EBNF grammar notation. The generated parsers can do automatic AST construction and intermediate code generation.

A set of tools for the design and implementation of the front-end part of translators. The SYNTAX tools allow the generation of analyzers and the compilation of source texts with those analyzers. This has all the capabilities of lex and yacc plus some additional features including better error processing, i.e. an automatic (and tunable) error repair and recovery mechanism.