RegexCraft

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Generating Code

Generating Code

Generate mode turns the current pattern, subject, replacement, and options into idiomatic snippets for many languages.

Open Generate

  • Click Generate in the toolbar or right panel, or press Ctrl+4.

Code for the default language (C#) appears immediately — no need to change the language dropdown first.

Options

  1. Language — C#, JavaScript, TypeScript, Python, PHP, Java, Go, Rust, Ruby, Perl, Kotlin, Swift
  2. Operation — IsMatch, Match (first), Matches (all), Replace, Split
  3. Review the snippet in the read-only editor
  4. Click Copy code to place it on the clipboard

Snippets update automatically when you change the pattern, subject, replacement, options, flavor, language, or operation.

What is included

  • Imports / usings where appropriate
  • Pattern and subject as properly escaped string literals
  • Option flags mapped to the language’s API when possible (e.g. RegexOptions.IgnoreCase, re.IGNORECASE, JS i/m/s flags)
  • Comments pointing at group access (Groups[1], match.group(1), etc.)
  • A short comment naming the source engine used in RegexCraft

Engine notes

RegexCraft can test with .NET, PCRE2, and JavaScript (Jint), plus approximate testing for other flavors. Generated code always targets the host language’s native API.

Language Runtime API Caveats
C# System.Text.RegularExpressions Closest to .NET flavor; includes match timeout
JavaScript / TypeScript RegExp ES2018+ for lookbehind / named groups
Python re Not full PCRE; consider regex package for advanced work
PHP preg_* PCRE under the hood
Java / Kotlin Pattern / Regex JVM dialect
Go regexp (RE2) No lookbehind / backreferences
Rust regex crate RE2-like; notes mention fancy-regex
Ruby Regexp Onigmo dialect
Perl m// s/// Illustrative snippets
Swift NSRegularExpression ICU-based

Always re-test generated code in the target runtime for edge cases. See also Flavors & testing fidelity.

Tips

  • Prefer Matches (all) when you want iteration samples.
  • Set a realistic replacement string before generating Replace snippets.
  • Switch flavor before generating if you want the “source engine” comment to match your target dialect family.
  • Generation requests are logged (language + operation) when you copy.