How to insert a "/" within a string?

rsvp1920 has asked for the wisdom of the Perl Monks concerning the following question:

Replies are listed 'Best First'.
Re: How to insert a "/" within a string? by moritz (Cardinal) on Feb 21, 2012 at 10:40 UTC
Something like `$str =~ s{CO}{C/O}g` maybe? See also: perlintro, perlretut. Perl 6 - second systems done right	[reply] [d/l]
Re^2: How to insert a "/" within a string? by bimleshsharma (Beadle) on Feb 21, 2012 at 11:06 UTC
This will also work... `my $string = 'ACOCOB'; $string =~ s/CO/C\/O/g; print "$string\n";` [download]	[reply] [d/l]
Re^3: How to insert a "/" within a string? by ikegami (Patriarch) on Feb 22, 2012 at 00:01 UTC
Yes, but he intentionally avoided using "/" as a delimiter to avoid "leaning toothpick syndrome".	[reply]
Re: How to insert a "/" within a string? by ambrus (Abbot) on Feb 21, 2012 at 11:25 UTC
Just write it as two mutually recursive functions: `$_ = "ABCOPCOGNHVCOHL"; my $P = sub { my($p, $q, $e, @s) = @_; $e, @s ? &{"C" ne $e ? $p : $q} +($p, $q, @s) : () }; my $Q = sub { my($p, $q, $e, @s) = @_; ("O" ne $e ? () : "/"), &$p($p, + $q, $e, @s) }; print join "", &$P($P, $Q, split //), "\n";` [download] (Don't take this answer seriously.)	[reply] [d/l]
Re^2: How to insert a "/" within a string? by choroba (Cardinal) on Feb 21, 2012 at 11:34 UTC
In fact, one should be inserting ⚡ instead of /, and it should go between C and D, not C and O: `$string = 'ACDC';` [download]	[reply] [d/l]
Re: How to insert a "/" within a string? by rovf (Priest) on Feb 21, 2012 at 10:43 UTC
Use the g-modifier of the substitution operator. For example: If `my $string = 'ACOCOB';` [download] then `$string =~ s(CO)(C/O)g; print "$string\n";` [download] prints AC/OC/OB -- Ronald Fischer <ynnor@mm.st>	[reply] [d/l] [select]
Re: How to insert a "/" within a string? by trizen (Hermit) on Feb 21, 2012 at 12:14 UTC
index + substr: `my $str = 'ABCOPCOGNHVCOHL'; my $index = 0; while (($index = index($str, 'CO', $index)) > -1) { substr $str, $index, 2, 'C/O'; } print "$str\n"; __END__ ABC/OPC/OGNHVC/OHL` [download]	[reply] [d/l]
Re^2: How to insert a "/" within a string? by rovf (Priest) on Feb 21, 2012 at 13:11 UTC
To be in the same spirit as most of the other solutions proposed here, you should have written `($index = index($str, 'CO', $index)) > -1` as `lc($index = index($str, 'CO', $index)) =~ /^-/` [download] ;-) -- Ronald Fischer <ynnor@mm.st>	[reply] [d/l] [select]
Re^2: How to insert a "/" within a string? by GrandFather (Saint) on Feb 21, 2012 at 19:41 UTC
Or using substr to insert a string between two characters: `$_ = 0; substr $str, $_ + 1, 0, '/' while ($_ = index $str, 'CO', $_) > -1;` [download] True laziness is hard work	[reply] [d/l]
Re: How to insert a "/" within a string? by oko1 (Deacon) on Feb 22, 2012 at 00:58 UTC
Why can't you guys just give a nice straight answer, like this one? `s/(?<O>\103)(?<C>\117)/$+{O}\057$+{C}/g;` [download] (This answer is just as serious as the ones before it, and the suggestions for appropriateness of usage still apply.) -- I hate storms, but calms undermine my spirits. -- Bernard Moitessier, "The Long Way"	[reply] [d/l]
Re: How to insert a "/" within a string? by ikegami (Patriarch) on Feb 22, 2012 at 00:04 UTC
In this case, `s{CO}{C/O}g` [download] would do. If there's a chance of overlap between the two patterns to separate (e.g. putting "/" between "AC" and "CA"), you need a lookahead. `s{AC(?=CA)}{AC/}g` [download] or `s{AC\K(?=CA)}{/}g` [download]	[reply] [d/l] [select]