You would have to do it with eval: 
use strict;
use warnings;

my $ref;
my ($A,$B);
while (<DATA>) {
  chomp;
  if (s/^\s+//) { eval "\$$ref = $_" }
  else {$ref = $_}
}
print "A=$A and B=$B\n";
__DATA__
A
 33
B
 22

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In reply to Re^3: regex issue by Roy Johnson
in thread regex issue by Anonymous Monk

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