Life & fun · alternatives · 2026

24 alternatives to Parsing a Reverse Polish Expression

Parsing a Reverse Polish Expression is a tool for evaluating mathematical expressions written in reverse Polish notation, where operators follow their operands rather than preceding them. It is designed for users who… Below are 24 products that do a similar job, ranked by how close each is in meaning and then by launch-day votes. Parsing a Reverse Polish Expression launched in 2022; newer entries below may have overtaken it.

1
Transductive regular expressions for text editing▲263
An extension of regular expressions for text editing, with a grep-like command-line tool. If you, like me, struggle with group logic in regular expressions, you might find it useful. I wanted to do this for a very long time. It is more of a sketch or prototype. I'd really appreciate your feedback!
2025 · github.com · its alternatives →
2
Regex library▲276
A curated list of most commonly used regular expressions
2022 · uibakery.io · its alternatives →
3PA
Parinfer – a simpler way to write Lisp▲674
Parinfer - simpler Lisp editing
2015 · shaunlebron.github.io · its alternatives →
4
How to write a recursive descent parser▲347
2017 · craftinginterpreters.com · its alternatives →
5
AnyParser Pro▲602
Parse multi-language images and documents into JSON/markdown
2025 · cambioml.com · its alternatives →
6
Using Parsing Expression Grammars to rewrite source code▲63
An example of PEG usage. Contribute to sebcat/move-literals development by creating an account on GitHub.
2016 · github.com · its alternatives →
7RL
Risp – Lisp in Rust▲314
Read Essays by Stepan Parunashvili
2019 · m.stopa.io · its alternatives →
8
RegexLearn▲328
Learn RegEx step by step, from zero to advanced
2021 · regexlearn.com · its alternatives →
9CD
Clojure DSL for pattern-matching, parsing and generic programming▲204
2012 · scattered-thoughts.net · its alternatives →
10
RegExr 2.0▲101
Online tool to learn, build, & test Regular Expressions
2014 · regexr.com · its alternatives →
11
Cronexpr, a Rust library to parse and iter crontab expression▲160
`cronexpr` is a library to parse and drive the crontab expression.
2024 · docs.rs · its alternatives →
12
Regex Derivatives (Brzozowski Derivatives)▲103
A Python sketch of a regex engine in less than 150 lines of code
2023 · github.com · its alternatives →
13
Parsers▲297
Extract structured data and visualize it without code
2019 · parsers.me · its alternatives →
14
Using functions to construct Regex in Python▲105
Python to Regex. Regex to Python. The yRegex for humans. - iogf/crocs
2017 · github.com · its alternatives →
15
Prig – like AWK, but uses Go for “scripting”▲77
Describes Prig, which is for Processing Records In Go. It's a text processing tool like AWK, but it uses Go as the scripting language.
2022 · benhoyt.com · its alternatives →
16
COBOL-REKT, a toolkit for analysing and reverse-engineering COBOL▲91
This is an evolving toolkit of capabilities helpful for analysing and reverse engineering legacy Cobol code. Currently, the following capabilities are available: - Program / Section-level flowchart generation based on AST (SVG or PNG) - Parse Tree generation (with export to JSON) - Control Flow Tree generation (with export to JSON) - Allows embedding code comments as comment nodes in the graph - The SMOJOL Interpreter (WIP) - Injecting AST and Control Flow into Neo4J - Injecting Cobol data layouts from Data Division into Neo4J (with dependencies like MOVE, COMPUTE, etc.) + export to…
2024 · github.com · its alternatives →
17
An expression parser supporting multiple types▲33
This C library is part of a main project aimed at providing a reactive key-value (KV) database. The data is typed (numbers, strings, dates, or booleans) and can include formulas with references to other entries. Clients connected to this database receive a real-time data stream with updates to the subscribed keys, allowing them to react to changes and their dependencies. Essentially, it’s like building a distributed Excel, where data and formulas dynamically update across the system. I couldn’t find any libraries that offered the full set of features I needed for evaluating expressions, so I…
2024 · github.com · its alternatives →
18
An experimental data-flow analysis tool for JavaScript▲95
Find the origin of any character in the DOM
2019 · fromjs.com · its alternatives →
19RE
Regular expression compilation visualized▲219
2021 · compiler.org · its alternatives →
20
ut – Rust based CLI utilities for devs and IT▲170
Hey HN, I find myself reaching for tools like it-tools.tech or other random sites every now and then during development or debugging. So, I built a toolkit with a sane and simple CLI interface for most of those tools. For the curious and lazy, at the moment, ut has tools for, - Encoding: base64 (encode, decode), url (encode, decode) - Hashing: md5, sha1, sha224, sha256, sha384, sha512 - Data Generation: uuid (v1, v3, v4, v5), token, lorem, random - Text Processing: case (lower, upper, camel, title, constant, header, sentence, snake), pretty-print, diff - Development Tools: calc, json…
2025 · github.com · its alternatives →
21
A PHP parser written in PHP▲77
A PHP parser written in PHP. Contribute to nikic/PHP-Parser development by creating an account on GitHub.
2012 · github.com · its alternatives →
22PA
Parsr – A toolchain to transform documents into usable structured text▲182
2020 · par.sr · its alternatives →
23AC
A complete Bash parser in JavaScript transpiled from Go▲89
2018 · npmjs.com · its alternatives →
24ID
I designed a language for code golf, compiling to Common Lisp▲102
2013 · rhoscript.com · its alternatives →

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Ranked by how close each launch is in meaning, then by votes. Prices were read from each product’s own site when checked and can change. Refine with your own description →