[SOLVED] lazy +?

vincix · 04-11-2017, 08:48 AM

Hi,

If I write this:

Code:

echo "This is <EM>string</EM>" | grep -E '<.+?>'

I get the folowing highlight:

Code:

This is a <EM>string</EM>

Why is it all highlighted instead of only the occurrences of "<EM>"?

I also tested it on regex sites (regex101.com) and it works fine. Why does grep behave differently?

rknichols · 04-11-2017, 09:10 AM

It's because grep does not, by default, support lazy regex. You can try using the "-P" (--perl-regexp) option which asks grep to interpret the pattern as a Perl regex. Note that Perl regex is not fully supported in grep.