c:\@Work\Perl\monks\Learning_Perl_2017>perl xform_nested_terms_1.pl
#
# ----- testing xform_4() -----
#
ok 1 - ()
ok 2 - ()'
ok 3 - (()')'
ok 4 - ((()')')'
ok 5 - (()' (()')')'
ok 6 - (A & B)
ok 7 - (A & B)'
ok 8 - (A & B | (C & D)')'
ok 9 - ((A & B)' | (A & C & (A & B & D)'))
ok 10 - ((A | B)' & (C | (D & (E & F)))')'
ok 11 - ((A & B)' | (A & C & (A & Boff' & D | (A & (B' & D)')'))
1..11
ok 12 - no warnings
1..12