How to escape metacharacters without backslash it in regex?

aurekha has asked for the wisdom of the Perl Monks concerning the following question:

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Re: How to escape metacharacters without backslash it in regex? by moritz (Cardinal) on Dec 17, 2007 at 13:49 UTC
You can escape meta chars with `\Q...\E`, and you can do something like `my $good_re = quotemeta $evil_re; m/$good_re/;` [download] But both methods use backslashes under the hood as well. Perl 6 regexes will have `'...'` and `"..."` quoting (and implicit grouping), there you don't need backslashes at all.	[reply] [d/l] [select]
Re: How to escape metacharacters without backslash it in regex? by Joost (Canon) on Dec 17, 2007 at 13:50 UTC
`/\Q$string\E/` see Quote and Quote-like Operators and quotemeta. "What should it profit a man, if he should win a flame war, yet lose his cool?"	[reply] [d/l]
Re: How to escape metacharacters without backslash it in regex? by swampyankee (Parson) on Dec 17, 2007 at 13:54 UTC
Why? Why? Why? First, a little bit of explanation as to why you need to do this (and "because I want to" is not a good reason). Second, have you read the Perl Regular Expressions and Perl Regular Expressions Tutorial? If not, please do so. I suspect that what you need to do is either use `\Q` and `\E` or quotemeta. If those don't do the trick, post an explanation of why they don't fit your requirements, and the code and data that are giving you trouble. emc Information about American English usage here and here. Any Northeastern US area jobs? I'm currently unemployed.	[reply]
Re: How to escape metacharacters without backslash it in regex? by toolic (Bishop) on Dec 17, 2007 at 13:49 UTC
Could you be more specific? What characters are you trying to include in your regex? What have you tried already (show us your code) and why does it not work for you (show us sample input, expected output, and actual output). Have you looked at perlretut?	[reply]
Re: How to escape metacharacters without backslash it in regex? by ikegami (Patriarch) on Dec 17, 2007 at 19:36 UTC
or use `index`. `index($str, $substr) >= 0` [download] is equivalent to `$str =~ /\Q$substr\E/` [download] and `my $re = quotemeta($substr); $str =~ /$re/` [download]	[reply] [d/l] [select]