Re: Still having trouble with regexes! Please help

[AnomalousMonk]

Update: The approach discussed in this reply has a problem. Don't use it. For a fix, see my reply below.

This needs the Perl version 5.10 regex extensions and defined-or operator, the latter not critical. This approach needs extensive testing to be trusted. (Update: Some more testing done with the test cases used by choroba in his reply in your other thread gives me a bit more confidence in this approach, but you must still thoroughly test!)

c:\@Work\Perl\monks>perl -wMstrict -le
"use 5.010;
 ;;
 my $x = q{((A & B)' | (A & C & (A & B & D | (A & (B' & D)')'))};
 print qq{:$x:};
 ;;
 my $parenthetic = qr{ ( [(] (?: [^()]*+ | (?R))* [)] ) }xms;
 my $term        = qr{ ( [[:alpha:]] \w* ) }xms;
 ;;
 1 while $x =~ s{ (?: $parenthetic | $term) \x27 }{ '!' . ($1 // $2) }
+xmsge;
 print qq{:$x:};
"
:((A & B)' | (A & C & (A & B & D | (A & (B' & D)')')):
:(!(A & B) | (A & C & (A & B & D | !(A & !(!B & D)))):

(Note that my REPL does not like unbalanced single-quote characters, so I use  \x27 instead of a single single-quote at one point.) There is probably a more elegant way to express and use these regexes, but it's late...

Update 1:

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))))

I assume that the single-quote after the  !(A & B)' term as quoted from the OP should not be there. If so, please update the OP.

Update 2:

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

Do yourself a favor and choose a different delimiter when the delimiter character appears in the delimited string:
    my $x = q{((A & B)' | (A & C & (A & B & D | (A & (B' & D)')'))};