Hello Friends

We still seem to have trouble getting the regex to work correctly!

Here is the original expression:

my $x ='((A & B)\' | (A & C & (A & B & D | (A & (B\' & D)\')\'))';

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From the original value of $x printed above, we have to create the following slightly modified expression, like below:

(!(A & B) | (A & C & (A & B & D | !(A & !(!B & D))))

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Our Perl program looks like this right now:

#!/usr/bin/perl
use strict;
use warnings;
my $x = '((A & B)\' | (A & C & (A & B & D | (A & (B\' & D)\')\'))'; 

print "Given: $x\n"; 

$x =~ s/(\(\s*[^()]+\s*\))\'/\!$1/g; 

print "Calculated: ",$x,"\n"; $x =~s/([a-zA-Z]\w*)\'/\!$1/g; 

$x =~ s/((\(){1}\s*.*?([!][(])+.*?\)\s*)\'/\!$1/g;

print "NewVl : ",$x,"\n";

[download]

I think we have to get it right on how to handle the nested ' single code character (BTW, ' is for representing negation of a value or a logical expression in one tool and we are trying to replace that single quote character to ! character, which is needed in another tool, and print it like stated above).

Thanks for the continued huge help. Bill

In reply to Still having trouble with regexes! Please help by Learning_Perl_2017

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