About

RPA Library

The Regular Pattern Analyzer Library (RPA) is a top-down recursive parser and pattern matching engine. The input grammar notation is Backus–Naur Form (BNF) and the produced output is a browsable Abstract Syntax Tree (AST). The grammar allows Regular Expressions, so the parser can also be used as RegEx or search engine. The execution engine supports muti-threading and it can parse multiple input streams simultaneously.

  • Features

  • - Backus–Naur Form (BNF)
  • - Produces a browsable Syntax Tree
  • - Regular Expressions
  • - Input Encodings: UTF8, UTF16
  • - Case sensitive/insensitive searching or parsing
  • - Left-Recursive expressions (direct and indirect)
  • - Right-Recursive expressions (direct and indirect)
  • - Multi-Threading.

If you would like to see the RPA engine in action, please check out the Online Demo

REX Library

The Regular Expressions Library (REX) is a Deterministic Finite Automata (DFA) implementation. One of the key features in REX is the native support for wide characters. By default REX uses 32-bit integer to encode the transtion symbols, but this could be redefined at build time to any other integral data type. REX will NOT split wide characters across multiple DFA states as other implementations supporting wide characters do. REX will always generate the same number of DFA states for a given regular expression complexity no matter what type and size of symbols are used.

If you would like to experiment with REX please check out REX Grep program.