Tools for generating regular expressions

Pattern Seekers

© Photo by JJ Ying on Unsplash

© Photo by JJ Ying on Unsplash

Article from Issue 251/2021

As regular expressions grow in complexity, regex generators can make the job easier by computing the patterns for you.

A regular expression (regex) [1] is a sequence of characters that describes a search pattern. You can use a regex to save time searching and replacing in texts, such as strings in programming languages, database query results, or normal documents. Regexes also can help you effectively use utilities, such as grep [2], xmlgrep [3], and ugrep [4].

Ultimately, a regex's usefulness depends on the pattern you select. Formulating a regex that delivers precise results is no easy task (see the "DIY Regular Expressions" box). To save time, a regex generator can automate this step for you by taking a text/character string and deriving a suitable regular expression.

Regex generators work with varying degrees of precision. Some regex generators offer maximum precision, where the regular expression finds exactly one pattern. Others offer minimum precision, where the regex finds a set of patterns with a similar structure. In this article, I test several regex generators to determine how well they work (see also the "Nonfunctional" box).


Use Express-Checkout link below to read the full article (PDF).

Buy this article as PDF

Express-Checkout as PDF
Price $2.95
(incl. VAT)

Buy Linux Magazine

Get it on Google Play

US / Canada

Get it on Google Play

UK / Australia

Related content

  • ICgrep

    One of the most common tasks when working on computers involves browsing texts for search patterns. Here, ICgrep offers a modern, parallel, and Unicode-enabled alternative to the classic grep.

  • Command Line: Grep

    Once you understand the intricacies of grep, you can find just about anything.

  • Simple Regex Language

    Regular expressions are a powerful tool, but they can also be very hard to digest. The Simple Regex Language lets you write regular expressions in natural language.

  • agrep

    The agrep tool expands on grep by adding fuzzy search capabilities to text string-matching operations.

  • Free Software Projects

    Redet helps you create regular expressions, and solving Go problems is a good way to relax. We also examine the latest events at Debian, including recent talk about the GNU Free Documentation License.

comments powered by Disqus

Direct Download

Read full article as PDF:

Price $2.95