Michael Lazzaro wrote:
> Damian Conway wrote:
>
> > "you can leave a comma out either side of a block/closure, no matter
> > where it appears in the argument list"
>
> Hmm. I had been figuring the all conditional/loop stuff would be
> special cases within the grammar, because of their associated cruft...
> but if comma-optional is allowed on *either* side of any block, it
> means that their grammar becomes quite trivial.
>
> That wins the less-special-cases war by a mile, so I emphatically
> withdraw my objection.
Ah. It was only on reading that (and discovering that you hadn't
previously known about the 'optional comma with closure argument' rule)
that I understood why you had previously been so in favour of proposed
new syntaxes: through a desire to banish the Perl 5 syntax.
Mike, now you've come to terms with the Perl 5 syntax, do you still find
right-left pipelines as compelling as you've previously argued?
It seems that when chaining together functions, omitting C<< <~ >>
operators gives the same result in the familiar Perl 5 standard
function-call syntax:
@foo = sort { ... } <~ map { ... } <~ grep { ... } <~ @bar;
@foo = sort { ... } map { ... } grep { ... } @bar;
Left-right pipelines make sense to me. I'm not yet sure how much I'd
use them, but there are times when I find it a little odd to have data
flowing 'upstream' in code, and reversing this could be nifty.
However right-left pipelines don't seem to add much to the language,
while becoming something else to have to learn and/or explain.
(Damian's explanation of what C<< <~ >> does to code seemed
significantly more involved than that of C<< ~> >>.) And an alternative
spelling for the assignment operator[*0] doesn't strike me as something
Perl is really missing:
$msg <~ 'Hello there';
$msg = 'Hello there';
I realize that there's a symmetry between the two operators, but that
isn't a convincing reason for having them both. People are used to data
flow in one direction; it seems reasonable only to have an operator when
wanting to change this, to make it go in the opposite direction.
What benefit does C<< <~ >> bring to the language?
Smylers
