$ perl -le'for( qw/foo bar baz blah/ ){ print int scalar( /b/ .. // ) }'
0
1
1
1
$ perl -le'for( qw/foo bar baz quux/ ){ print int scalar( /b/ .. // ) }'
0
1
1
0

##</code><code>##

$ perl -le'for( qw( foo bar baz quux ), "" ){ print int scalar( /b/ .. /$^/ ) }'
0
1
2
3
4
$ perl -le'for( qw( foo bar baz quux ), "" ){ print int scalar( /baz/ .. /$^/ ) }'
0
0
1
2
3

##</code><code>##

log_failure()
    unless grep {
        ( exists $hash{$_} and ( do_something($_), 1 ) )
        .. /$^/
    } @options;