Ruby: Making your regular expressions more readable with /x and alternative delimiters

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The following two hints are taken from Github's Ruby style guide Show snapshot :

If your regular expression mentions a lot of forward slashes, you can use the alternative delimiters %r(...), %r[...] or %r{...} instead of /.../.


If your regular expression is growing complex, you can use the /x modifier to ignore whitespace and comments:

regexp = %r{
  start         # some text
  \s            # white space char
  (group)       # first group
  (?:alt1|alt2) # some alternation

If you would like to match whitespace characters, you have to escape them if they are not contained in a character class.

More tools to simplify regular expessions

Henning Koch
Last edit
Henning Koch
readability, regex, multiple, lines, multi-line
Source code in this card is licensed under the MIT License.
Posted by Henning Koch to makandra dev (2012-04-03 09:40)