Search Results for "backtracking"

RE2 is a fast, safe, thread-friendly alternative to backtracking regular expression engines like those used in PCRE, Perl, and Python. It is a C++ library. This is the source code repository for RE2, a regular expression library. There is a fair amount of documentation (including code snippets) in the re2.h header file. Unless otherwise noted, the RE2 source files are distributed under the BSD-style license found in the LICENSE file.

RE2/J is a high-performance regular expression engine implemented in pure Java as a port of Google’s C++ RE2 library. Unlike traditional regex engines such as Java’s java.util.regex, PCRE, or Perl’s implementation—which rely on backtracking and can suffer from catastrophic exponential runtimes—RE2/J guarantees linear-time matching relative to input size. It achieves this efficiency by simulating all possible matches in a single pass using a nondeterministic finite automaton (NFA), ensuring predictable and safe performance even with complex patterns. This makes RE2/J ideal for applications that must handle user-supplied regular expressions securely without the risk of denial-of-service through regex backtracking. ...

Parser library that uses an EBNF like grammar to generate a parse tree You can use it to create a quick parser It uses backtracking so it may be slow for some grammar rules

...The spg tool takes .parser files that contain descriptions of parsers as input and produces C++ source code for parser classes as output. The parser generator produces a recursive descent top-down backtracking parser that use the lexical analyzer generated by slg to tokenize the input.

...The material covers arrays, linked lists, stacks, queues, recursion, sorting, binary search, hash tables, strings, trees, heaps, and graphs. More advanced examples address backtracking, divide-and-conquer methods, dynamic programming, shortest paths, topological sorting, caches, and priority queues. Solutions are available across numerous languages, including C, C++, Java, Go, Python, JavaScript, Rust, Swift, Kotlin, and TypeScript. This multilingual layout helps learners compare syntax and implementation choices while studying the same concepts. ...

A backtracking (non-packrat) parser generator for parsing expression grammars. The parsers are generated at run-time using the LLVM JIT compilation engine.