add subs from $?PACKAGE.HOW ?

[Marc Chantreux]

hello,

i'm trying to ease the production of xml streams in a perl6 script so i
wrote  

    sub _attrs_str ( %attrs) {
        %attrs.pairs.map: { qq/{.key}="{.value}"/ }
    }  

    multi sub tag ( Str $tag, Parcel $attrs=()) {
        "<{ $tag, _attrs_str $attrs.hash }/>";
    }

    multi sub tag ( Parcel $spec ) { tag $spec[0], $spec[1..*] }


now i can write 

    say tag < img src /images/logo.png >;

to produce  

    <img src="/images/logo.png"/>

the next step is to write  

    say img < src /images/logo.png >;

to get the same content. i also want to have link and meta helpers. what
i would like to write is 

    $?PACKAGE.
    < link meta img >.map: {
        $?PACKAGE.^add_method\
        ( $?PACKAGE
        , $_
        , &tag.assuming( tag => $_ ) )
    }

but $?PACKAGE.HOW is a PackageHOW and add_method comes with ClassHOW. if
someone can give me some clue ? 

thanks and regards
-- 
Marc Chantreux
Université de Strasbourg, Direction Informatique
14 Rue René Descartes,
67084  STRASBOURG CEDEX
☎: 03.68.85.57.40
http://unistra.fr
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