Using 'ord' in a regular expression for substitution

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

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Re: Using 'ord' in a regular expression for substitution by Corion (Patriarch) on Aug 25, 2010 at 15:03 UTC
ord doesn't work that way at all, and regular expressions don't either. Maybe you want this: `my $to_replace = chr(226); $string =~ s/\Q$to_replace/'/gi;` [download]	[reply] [d/l]
Re: Using 'ord' in a regular expression for substitution by ikegami (Patriarch) on Aug 25, 2010 at 15:29 UTC
`my $char = chr(226); my $pat = quotemeta($char); # Create pattern that matches string s/$pat/'/ig;` [download] `my $char = chr(226); s/\Q$char\E/'/ig; # Alternate way of calling quotemeta` [download] `s/\xE2/'/ig; # 0xE2 == 226` [download]	[reply] [d/l] [select]
Re: Using 'ord' in a regular expression for substitution by jwkrahn (Abbot) on Aug 25, 2010 at 15:24 UTC
You don't really need to use a regular expression: `$string =~ tr/\342/'/;` [download] But if you really want to: `$string =~ s/\342/'/g;` [download]	[reply] [d/l] [select]
Re^2: Using 'ord' in a regular expression for substitution by JavaFan (Canon) on Aug 25, 2010 at 15:29 UTC
There is a difference. The OP uses `/i`. If `$string` has the UTF-8 flag set both â and Â will match `$r = chr 226; s/$r/'/ig;`. And if UTF-8 isn't set, there still may be a locale that plays a role.	[reply] [d/l] [select]
Re: Using 'ord' in a regular expression for substitution by JavaFan (Canon) on Aug 25, 2010 at 15:04 UTC
Uhm, `ord` is used to get the code point number given a single character string. Perhaps you mean `chr`? `s/${\(chr(226))}/'/ig;` [download] But there's a simpler way. 226 decimal is E2 in hex: `s/\x{E2}/'/ig;` [download]	[reply] [d/l] [select]
Re: Using 'ord' in a regular expression for substitution by roboticus (Chancellor) on Aug 25, 2010 at 15:07 UTC
You don't. Try instead: `# Build a regular expression: my $regex = qr/ord(226)/i; # Use it to alter $string: $string =~ s/$regex/'/g;` [download] Having said that, I doubt you want to use `ord`, as it converts a character into a number. I suspect you want `chr` which turns the number into a character... Update: Ignore this stupid post, please. ...roboticus	[reply] [d/l] [select]
Re^2: Using 'ord' in a regular expression for substitution by JavaFan (Canon) on Aug 25, 2010 at 15:24 UTC
What makes you think that `$r = qr/STRING/i; s/$r/REPL/g;` would work where `s/STRING/REPL/ig;` doesn't? `qr/ord(226)/` fails in exactly the same way `s/ord(226)/'/ig;` does. Both match `"ord226"` and set (if matched) $1 to `226`.	[reply] [d/l] [select]