The parameters received from the command line, are always Str (or IntStr if
they look like an integer). To allow direct matching / handling of this, we
would need something like an EnumStr type. I don’t think that’s going to
happen soon.
I also tried some pre-processing on the @*ARGS array in an INIT block, but that
fails because the default command line processing really expects something that
works like a Str.
So, so far I’ve only been able to come up with this workaround:
sub MAIN(:$country! where (Country.enums{$_}:exists)) {
…
}
Unfortunately it will display the feedback on a wrong parameter like:
Usage:
script.pl --country=<Any>
but I guess that’s the best we have for this in the short-term.
> On 18 Nov 2016, at 15:40, Itsuki Toyota (via RT)
> <perl6-bugs-follo...@perl.org> wrote:
>
> # New Ticket Created by Itsuki Toyota
> # Please include the string: [perl #130131]
> # in the subject line of all future correspondence about this issue.
> # <URL: https://rt.perl.org/Ticket/Display.html?id=130131 >
>
> See the following results:
>
> $ perl6 script.p6 --country=America
> Usage:
> script.p6 --country=<Country>
>
> $ perl6 script.p6 --country=1
> Usage:
> script.p6 --country=<Country>
>
>
> script.p6:
> ----
> use v6;
>
> enum Country<China America Brazil>;
>
> sub MAIN(Country :$country!) {
> say $country;
> }
> ----
>
> $ perl6 --version
> This is Rakudo version 2016.10-295-g85c7072 built on MoarVM version
> 2016.10-71-g9d5c874
> implementing Perl 6.c.
>
>
> I think that if sub MAIN cannot accept enum argument, it should display any
> error messages and die.
