I personally would recommend using a constant if there's a possibility of constant folding:
#!/usr/local/bin/perl
use O qw/ Deparse /;
use constant CONDITION => 0;
if( CONDITION ) {
print "condition true\n";
} else {
print "condition false\n";
}
__END__
## and here's the output. notice that there are
## no if's
me@myhost> ./test.pl
./test.pl syntax OK
sub CONDITION () {
package constant;
$scalar;
}
print "condition false\n";;
Otherwise I guess I could care less, but I use it more for a mental note than anything else -- it makes me aware that this value should be a constant