>>>>> "Matthew" == Matthew Walton <[EMAIL PROTECTED]> writes:
Matthew> Perl 6 has formal parameters for subs, methods etc. I don't see any
Matthew> mention of Perl 5-style prototypes in S6, and I honestly can't see how
Matthew> they could possibly fit with formal parameters. Hopefully Larry or
Matthew> someone can clarify whether they still exist or not.
As long as you can have a user-defined null-prototyped subroutine (one
that doesn't need parens following), you have the problem. See the
sin/time examples in the monk article, and then consider user-defined
functions that have no args (like time) and those that do (like sin).
Matthew> The Perlmonks article throws up a lot of very nasty cases. Not knowing
Matthew> the entire current language definition by heart, I can't say this with
Matthew> absolutely certainty, but I retain the belief that Perl 6 is at least
Matthew> *easier* to deal with than Perl 5.
I believe you have a false belief. I don't know anything in the new
prototypes-which-became-full-formal-arguments that made it any
*easier* to recognize the ending of a subroutine argument list without
knowing its precise definition.
In Perl6:
sub no_args () { ... }
sub list_args ([EMAIL PROTECTED]) { ... }
no_args / # this is a divide
list_args / # this is the start of a regex
See, it's still there. :)
Matthew> It is also possible that telling the difference between /-as-divide
Matthew> and /-as-regex becomes much easier if lookahead is employed in the
Matthew> tokeniser.
No, not possible at all. The entire rest of the program may be valid
either way. You *must* know by the time you're done with /, or
/-and-more. The rest of the code cannot be a hint. Again, see my
article.
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