CodeCrafters
Build your own grep
Learn about regex syntax: character classes, quantifiers and more
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Regular expressions (or Regexes) are patterns used to match character combinations in strings. In this challenge, you'll build a Regex engine from scratch by recreating grep, a CLI tool for regex-based searching.
Along the way you'll learn about Regex syntax, character classes, quantifiers and more.
Base Stages
Regular expressions (or Regexes) are patterns used to match character combinations in strings. In this challenge, you'll build a Regex engine from scratch by recreating grep, a CLI tool for regex-based searching.
Along the way you'll learn about Regex syntax, character classes, quantifiers and more.
Backreferences
In this challenge extension, you'll add support for backreferences to your Grep implementation.
Along the way, you'll learn about how capture groups and backreferences work.
File Search
In this challenge extension, you'll add support for searching files.
Along the way, you'll learn about how to implement efficient file I/O, directory traversal and pattern matching on file contents.
Quantifiers
In this challenge extension, you'll add support for quantifiers to your Grep implementation.
Along the way, you'll learn about how to implement the * quantifier (zero or more), and bounded quantifiers.
Ananthalakshmi Sankar
Automation Engineer at Apple
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I think the instant feedback right there in the git push is really cool.
Didn't even know that was possible!
Patrick Burris
Senior Software Developer, CenturyLink