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Postings from July 2013
On Fri, Jul 5, 2013 at 10:24 AM, Father Chrysostomos <sprout@cpan.org> wrote:
> rjbs:
>> Edge cases
>
> If foo->@* means @foo, then does foo->@*[0] mean @foo[0]? That is
> useless if we have foo->@[0].
>
> If we have foo->@[0] and extend it to all sigils, we end up with:
the advantage of simply allowing postfix in addition to circumfix with
the same symbols
is, there are no other complications.
@{foo} would be allowed to be written as foo@{}, and the other
accesses into it would remain the same. foo@{}[0] is a slice with a
single element, foo${}[0] is an element access
> $_->*{foo} # means *$_{foo}
the glob referred to by the globref in $_ is considered as a hash and
we access the value in the slot named "foo" Adding the implied curlies
gives *{$_}{foo} and in simple postfix syntax that would be $_*{}{foo}
> $_->${foo} # means $$_{foo} (i.e., $_->{foo})
> $_->&(foo) # means $&_{foo} (i.e., $_->(foo))
>
> The last two are useless. The dollar form steals existing syntax.
First one: $_ contains a hashref and we want to look up the thing in
the foo slot. We have the skinny arrow postfix syntax for this
already; simple postfix brackets would give yet another
way to fully spell it out: in addition to ${$_}{foo} and $_->{foo}
there would be $_${}{foo}
Second one: if we're trying to call the coderef in $_ with an argument
of foo, &{$_}(foo), the circumfix ampersand dereference could become
postfix as $_&{}(foo).
if the empty curlies become optional, that would give a tight-binding
prefix sigil, a loose-binding postfix sigil, and circumfix (prefix
plus curlies) for when you need an intermediate grouping.
@foo and foo@ would mean the same thing. @foo@ would continue to be nonsense.
$foo[0] could get written foo$[0].
> *$_{foo}
could be written as $_*{foo}
> $_->{foo}
could be written as $_${foo}
> $_->(foo)
could be written as $_&(foo)
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