my $fmt = $opt->{$ofmt_key};
$fmt = lc($fmt) if defined $fmt;
- if ($dst =~ s/\A([a-z0-9]+)://is) { # e.g. Maildir:/home/user/Mail/
+ if ($dst =~ m!\A([a-z0-9\+]+)://!is) {
+ defined($fmt) and return $lei->fail(<<"");
+--$ofmt_key=$fmt invalid with URL $dst
+
+ $fmt = lc $1;
+ } elsif ($dst =~ s/\A([a-z0-9]+)://is) { # e.g. Maildir:/home/user/Mail/
my $ofmt = lc $1;
$fmt //= $ofmt;
return $lei->fail(<<"") if $fmt ne $ofmt;