Re: How to make these reg exp changes?

Your solutions work OK - thanks to both of you!
But I have a question (maybe I should have written this before):
What I must change is:

....MMMMiiii => ooooMMMMiiii
....MMMMoooo => iiiiMMMMoooo
iiiiMMMM.... => iiiiMMMMoooo
ooooMMMM.... => ooooMMMMiiii
[download]

I mean, If you do not have some character before the '.' , how will it understand to replace for example, '.' with 'I' if I have 'O' after the string of 'M'? Is there any chance that this can be done?

Comment on Re: How to make these reg exp changes? Download Code

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Re^2: How to make these reg exp changes? by ikegami (Patriarch) on Nov 15, 2009 at 23:39 UTC
`$ perl -wle' my %neg = ( o => "i", i => "o" ); while (<>) { chomp; s/([io])(M)(\.+)/ $1.$2.( $neg{$1} x length($3) ) /eg; s/(\.+)(?=M([io]))/ $neg{$2} x length($1) /eg; print; } ' ....MMMMiiii ....MMMMoooo iiiiMMMM.... ooooMMMM.... ooooMMMMiiii iiiiMMMMoooo iiiiMMMMoooo ooooMMMMiiii` [download] Simpler version that only works with Perl 5.10+: `$ perl -wle' my %neg = ( o => "i", i => "o" ); while (<>) { chomp; s/([io])M\K(\.+)/ $neg{$1} x length($2) /eg; s/(\.+)(?=M([io]))/ $neg{$2} x length($1) /eg; print; } ' ....MMMMiiii ....MMMMoooo iiiiMMMM.... ooooMMMM.... ooooMMMMiiii iiiiMMMMoooo iiiiMMMMoooo ooooMMMMiiii` [download] I could have used `-p` above, but I wanted to make clear that `%neg` only needs to be initialized once without complicating the issue by adding a `BEGIN`. Here's the 5.10+ version using `-p`: `perl -ple' BEGIN { %neg = qw( i o o i ) } s/([io])M\K(\.+)/ $neg{$1} x length($2) /eg; s/(\.+)(?=M([io]))/ $neg{$2} x length($1) /eg; '` [download] Update: Added \K version. \K rocks. Update: Added explanation about `-p`.	[reply] [d/l] [select]
Re^3: How to make these reg exp changes? by Anonymous Monk on Nov 16, 2009 at 00:09 UTC
exactly what I was looking for... The trick with the hash was just the thing! Thank you very much!	[reply]
Re^4: How to make these reg exp changes? by ikegami (Patriarch) on Nov 16, 2009 at 00:15 UTC
Honestly, the hash has nothing to do with the problem. `$neg{$1}` [download] is just short for `($1 eq 'o' ? 'i' : 'o')` [download]	[reply] [d/l] [select]
Re^4: How to make these reg exp changes? by Anonymous Monk on Nov 16, 2009 at 00:23 UTC
weird? `$s='III...MMMMMOOOO....MMMIIII'; print $s."\n"; %neg = ( O => "I", I => "O" ); $s=~s/([IO])(M)(\.+)/ $1.$2.( $neg{$1} x length($3) ) /eg; $s=~s/(\.+)(?=M([IO]))/ $neg{$2} x length($1) /eg; print $s;print "\n"; <code> It prints:<br> <code> III...MMMMMOOOO....MMMIIII IIIOOOMMMMMOOOOIIIIMMMIIII` [download]	[reply] [d/l]
Re^5: How to make these reg exp changes? by ikegami (Patriarch) on Nov 16, 2009 at 01:28 UTC