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Personally, I use regexes all the time. Every day. I'm constantly typing regexes into emacs and vim to do text manipulation. Sometimes a quick :%s/\(foo\|bar\)d

Personally, I use regexes all the time. Every day. I'm constantly typing regexes into emacs and vim to do text manipulation. Sometimes a quick :%s/\(foo\|bar\)d/baz\1/g, other times a :%v/function /d. I can't imagine what it would be like if I had to write out "begin with either of (number, letter, ..." I'd never get anything done. For programming it could be nice. It's an interesting idea. But I've found that good highlighting solves most of the problem. When I type "\\(" into emacs, it immediately highlights that \\( in a different color, along with \\| and \\). That way you can differentiate instantly between capture groups vs matching literal parens. Here's an example: http://i.imgur.com/b417O2o.png http://i.imgur.com/b417O2o.png That small snippet would become way, way longer if you use a regex combinator. Maybe good, maybe bad, but it's hard to read a lot of code. Yeah, it's ugly. And there are a bazillion small variations between regex engines. But for raw productivity, it seems hard to beat.

TAForObvReasons 10y ago
I find that most of the problems are resolved with interstitial comments a la perl /x or coffeescript heregex. Merely splitting the regular expression into smaller blocks with a short description of what to match makes it easy for people to verify the regular expression.
foxylad 10y ago
I, on the other hand, have to build a regex a few times a year. Every darn time I have to look up the difference between .* and .+, and how to do an "or", and why I get matches when I group a set of characters. So SRL sounds like a great idea: us mortals can use it to painfully stitch together our our poor regexes, and when we get good enough we can skip SRL and become fully fledged regex gods. Off topic, if SRL is a regex compiler, I'd love a regex decompiler. To be able to turn an impossible jumble of weird characters into a structured description of what it does would be hugely useful.
- tokenizerrr 10y ago
  RegexBuddy has a regex explainer, debugger, builder and tester. It works very well and supports exporting code to multiple languages and dialects
  - jmiserez 10y ago
    Also works on Linux (WINE), and can simulate different regex flavors. I can also recommend the webbased regex101.com, as it also supports non-JS regex flavors and explains things quite well.
Drup 10y ago
I think you misunderstand what "regex combinators" means. In particular, SRL is not regex combinators. TAForObvReasons in another answer posted this[1] that would explain it to you. [1]: https://groups.csail.mit.edu/mac/users/gjs/6.945/psets/ps01/.. https://groups.csail.mit.edu/mac/users/gjs/6.945/psets/ps01/.... About your example ... on the contrary, it would become way cleaner with regex combinators. The string manipulation would be replaced with proper composition and the escaping madness would disappear. For example (concat foo "\\|" bar "\||" baz) becomes (alt foo bar baz) You seem to be familiar with elisp. The lisp family is particularly adapted to combinators approach, please read the link above. :)
- sillysaurus3 10y ago
  If you like regex combinators, check out the elisp "rx" library. You can end up writing code sort of similar to the article's, with less emphasis on using english grammar: http://i.imgur.com/iD34MqC.png http://i.imgur.com/iD34MqC.png Combinators are very convenient and precise, but the tradeoff is that the code is longer. And I have to look up what to write every time I want to write one. But that's a personal bias. Thanks for the reference. I'll study it. EDIT: One of the good ideas in SRL is "if not followed by". There are too many [not]ahead-[not]behind combinations to warrant special syntax for each of them. I wonder if it could be streamlined, though?
- qwertyuiop924 10y ago
  ...wait a minute, that sounds a lot like SRE. If you don't know, SRE is a DSL in scheme that is essentially an alternate syntax for regex that does this, originally implemented by SCSH, and now most popularly by irregex. It looks like this: (w/nocase (: (=> name (+ (or alnum ("._%+-")))) "@" (=> domain (: (* (or alnum (".-"))) "." (>= 2 alpha))) eos)) I don't know if that's exactly what you were talking about: It's an alternate syntax, not a set of functions, which is what combinators usually imply.
rplnt 10y ago
I do most of my text manipulation in sublime text using replace. I like the interactivity of it compared to sed/awk, and the easy undo is helpful as well (try, back, edit, try, back, ..).

TAForObvReasons 10y ago

I find that most of the problems are resolved with interstitial comments a la perl /x or coffeescript heregex. Merely splitting the regular expression into smaller blocks with a short description of what to match makes it easy for people to verify the regular expression.

foxylad 10y ago

I, on the other hand, have to build a regex a few times a year. Every darn time I have to look up the difference between .* and .+, and how to do an "or", and why I get matches when I group a set of characters. So SRL sounds like a great idea: us mortals can use it to painfully stitch together our our poor regexes, and when we get good enough we can skip SRL and become fully fledged regex gods. Off topic, if SRL is a regex compiler, I'd love a regex decompiler. To be able to turn an impossible jumble of weird characters into a structured description of what it does would be hugely useful.

tokenizerrr 10y ago
RegexBuddy has a regex explainer, debugger, builder and tester. It works very well and supports exporting code to multiple languages and dialects
- jmiserez 10y ago
  Also works on Linux (WINE), and can simulate different regex flavors. I can also recommend the webbased regex101.com, as it also supports non-JS regex flavors and explains things quite well.

Drup 10y ago

I think you misunderstand what "regex combinators" means. In particular, SRL is not regex combinators. TAForObvReasons in another answer posted this[1] that would explain it to you. [1]: https://groups.csail.mit.edu/mac/users/gjs/6.945/psets/ps01/.. https://groups.csail.mit.edu/mac/users/gjs/6.945/psets/ps01/.... About your example ... on the contrary, it would become way cleaner with regex combinators. The string manipulation would be replaced with proper composition and the escaping madness would disappear. For example (concat foo "\\|" bar "\||" baz) becomes (alt foo bar baz) You seem to be familiar with elisp. The lisp family is particularly adapted to combinators approach, please read the link above. :)

sillysaurus3 10y ago
If you like regex combinators, check out the elisp "rx" library. You can end up writing code sort of similar to the article's, with less emphasis on using english grammar: http://i.imgur.com/iD34MqC.png http://i.imgur.com/iD34MqC.png Combinators are very convenient and precise, but the tradeoff is that the code is longer. And I have to look up what to write every time I want to write one. But that's a personal bias. Thanks for the reference. I'll study it. EDIT: One of the good ideas in SRL is "if not followed by". There are too many [not]ahead-[not]behind combinations to warrant special syntax for each of them. I wonder if it could be streamlined, though?
qwertyuiop924 10y ago
...wait a minute, that sounds a lot like SRE. If you don't know, SRE is a DSL in scheme that is essentially an alternate syntax for regex that does this, originally implemented by SCSH, and now most popularly by irregex. It looks like this: (w/nocase (: (=> name (+ (or alnum ("._%+-")))) "@" (=> domain (: (* (or alnum (".-"))) "." (>= 2 alpha))) eos)) I don't know if that's exactly what you were talking about: It's an alternate syntax, not a set of functions, which is what combinators usually imply.

rplnt 10y ago

I do most of my text manipulation in sublime text using replace. I like the interactivity of it compared to sed/awk, and the easy undo is helpful as well (try, back, edit, try, back, ..).