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I wish one of those regex libraries that replaces the regex symbols with human readable words would become standard. Or they don't work well? Regex is one of t

I wish one of those regex libraries that replaces the regex symbols with human readable words would become standard. Or they don't work well? Regex is one of those things where I have to look up to remind myself what the symbols are, and by the time I need this info again I've forgotten it all. I can't think of anywhere else in general programming where we have something so terse and symbol heavy.

db48x 9mo ago
It’s been done. Emacs, for example, has rx notation. From the manual: 35.3.3 The ‘rx’ Structured Regexp Notation ------------------------------------------ As an alternative to the string-based syntax, Emacs provides the structured ‘rx’ notation based on Lisp S-expressions. This notation is usually easier to read, write and maintain than regexp strings, and can be indented and commented freely. It requires a conversion into string form since that is what regexp functions expect, but that conversion typically takes place during byte-compilation rather than when the Lisp code using the regexp is run. Here is an ‘rx’ regexp(1) that matches a block comment in the C programming language: (rx "/*" ; Initial /* (zero-or-more (or (not "*") ; Either non-*, (seq "*" ; or * followed by (not "/")))) ; non-/ (one-or-more "*") ; At least one star, "/") ; and the final / or, using shorter synonyms and written more compactly, (rx "/*" (* (| (not "*") (: "*" (not "/")))) (+ "*") "/") In conventional string syntax, it would be written "/\\*\\(?:[^*]\\|\\*[^/]\\)*\\*+/" Of course, it does have one disadvantage. As the manual says: The ‘rx’ notation is mainly useful in Lisp code; it cannot be used in most interactive situations where a regexp is requested, such as when running ‘query-replace-regexp’ or in variable customization. Raku also has advanced the state of the art considerably.

db48x 9mo ago

It’s been done. Emacs, for example, has rx notation. From the manual: 35.3.3 The ‘rx’ Structured Regexp Notation ------------------------------------------ As an alternative to the string-based syntax, Emacs provides the structured ‘rx’ notation based on Lisp S-expressions. This notation is usually easier to read, write and maintain than regexp strings, and can be indented and commented freely. It requires a conversion into string form since that is what regexp functions expect, but that conversion typically takes place during byte-compilation rather than when the Lisp code using the regexp is run. Here is an ‘rx’ regexp(1) that matches a block comment in the C programming language: (rx "/*" ; Initial /* (zero-or-more (or (not "*") ; Either non-*, (seq "*" ; or * followed by (not "/")))) ; non-/ (one-or-more "*") ; At least one star, "/") ; and the final / or, using shorter synonyms and written more compactly, (rx "/*" (* (| (not "*") (: "*" (not "/")))) (+ "*") "/") In conventional string syntax, it would be written "/\\*\\(?:[^*]\\|\\*[^/]\\)*\\*+/" Of course, it does have one disadvantage. As the manual says: The ‘rx’ notation is mainly useful in Lisp code; it cannot be used in most interactive situations where a regexp is requested, such as when running ‘query-replace-regexp’ or in variable customization. Raku also has advanced the state of the art considerably.