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regexbashcygwingrep

Regex to get delimited content with egrep

I would like to get the parameter (without parantheses) of a function call with a regular expression.

I am using egrep in a bash script with cygwin.

This is what I got so far (with parantheses):

$ echo "require(catch.me)" | egrep -o '\((.*?)\)'
(catch.me)

What would be the right regex here?

Solution

  • http://www.greenend.org.uk/rjk/2002/06/regexp.html

    What are you looking for - is a lookbehind and lookahead regular expressions.

    Egrep cannot do that. grep with perl support can do that.

    from man grep:

     -P, --perl-regexp
          Interpret PATTERN as a Perl regular expression.  This is highly experimental and grep -P may warn of unimplemented features.

    So

    $> echo "require(catch.me)" | grep -o -P '(?<=\().*?(?=\))'
catch.me