while( <DATA> ) {
  chomp;
  print "( $_ ) = ( ", eval($_), " )\n";
}

##</code><code>##

use Math::Expression::Evaluator;

while( <DATA> ) {
  chomp;
  my $m = Math::Expression::Evaluator->new;
  eval {
    my $p = $m->parse($_);
    print "( $_ ) = ( ", $p->val, " )\n";
    1;
  } or warn "Unable to resolve expression ($_).\n";
}

__DATA__
1+2
1 + 2
2 * 2 + 4
asdf#@fg

##</code><code>##

( 1+2 ) = ( 3 )
( 1 + 2 ) = ( 3 )
( 2 * 2 + 4 ) = ( 8 )
Unable to resolve expression (asdf#@fg).