OK; let me get a quick clarification here. How does:
say "Hello, World!";
differ from:
"Hello, World!".say;
or:
say $*OUT: "Hello, World!";
in terms of dispatching? And more generally, would there be a
reasonable way to write a single routine (i.e., implementation) that
could be invoked by a programmer's choice of these calling
conventions, without redirects (i.e., code blocks devoted to the sole
task of calling another code block)?
Could you use binding?
my sub say (String *$first, String *...@rest, OStream :$out = $*OUT,
OStream :$err = $*ERR)
{ ... }
role String {
has &say:(String $first: String *...@rest, OStream :$out = $*OUT,
OStream :$err = $*ERR)
:= &OUTER::say;
}
That (or something like it) might be doable. But in the spirit of
TIMTOWTDI, I'd like to explore another possibility: what difficulties
would arise from allowing subs to have signatures with invocants,
which in turn allow the sub to be called using method-call syntax
(though possibly not method dispatch semantics)? In effect, allow
some syntactic sugar that allows properly-sigged subs outside of a
role to masquerade as methods of that role.
--
Jonathan "Dataweaver" Lang
