Re: improve ugly flow control

[FoxtrotUniform]

How about putting a "fail" sentinel at the end of @options and in %hash, such that do_something('fail') is the same as log_failure()? That way, your loop simplifies to:

foreach (@options) {
  if(exists $hash{$_}) {  # always true for $_='fail'
    &do_something($_); last;
  }
}

Now admittedly, inserting the sentinel into @options and %hash is obnoxious and hackish, but better to have that in your data than in your code....

[Aristotle]

In the same vein, but along a different angle:

foreach my $i ( 0 .. $#options, 'fail' ) {
    if( $i eq 'fail' ) {
        log_failure();
        last;
    }
    if( exists $hash{ $options[ $i ] } ) {
        do_something( $options[ $i ] );
        last;
    }
}