use "constant" function sigilless

ConstCaller.rakumod

=begin pod
Example Usage:

=begin code
use OpenGL::GLFW:from<Perl5> qw<:all>;
use lib ".";
use ConstCaller;

constant GLFW = ConstCaller.new :package(OpenGL::GLFW.WHO) :prefix<GLFW>;

say GLFW<PRESS>;
=end code
=end pod

#| Use &PREFIX_CONST as PREFIX<CONST>
class ConstCaller does Associative {
    has $.package;
    has $.prefix;

    method AT-KEY (Str:D $name) {
        $!package{'&' ~ $!prefix ~ '_' ~ $name}.()
    }
}