All --
A4 gives this example of C<for>:
for @foo -> $a, $b { ... } # "for @foo into $a and $b..."
but, this seems more natural to me (and, it turns out, closer to the P5
syntax for ill or good):
for $a, $b <- @foo { ... } # "for $a and $b from @foo..."
(heck, that even looks like shifting -- "shifty aliasing". The A4 syntax
looks like popping until you realize it is really shoving the left N
thingees into the containers on the right -- Syntactical Action at a
Distance).
Then, A4 gives this example of C<grep>:
grep -> $x { $x eq 3 } @list # "grep into $x, $ eq 3 from @list"
# NOTE: String comparison to a number...
But, this would match the C<for> example better, IMO (and puts the
alias name near the source of the things it will be aliasing):
grep { $x eq 3 } @list -> $x # "grep $x eq 3 where @list into $x"
My guess is that Larry wanted $x to appear before the block it
will be used in, and that C<grep>'s swapping of block and list
(when compared to C<for>) makes doing so ugly (IMO).
But, this would be more natural overall (again, IMO), following my
suggestion for C<for>, above:
grep { $x eq 3 } $x <- @list # "grep $x eq 3 where $x from @list"
Whether what I suggest makes sense to anyone else or not, I do
think the disparity between C<for> and C<grep> in A4 should be
dealt with...
------------------------------------------
Oh, and A4 also says "Standard Perl declarations will be plainly
marked with C<my> or C<our>." The C<< -> >> or C<< <- >> notation
for what amounts to a C<my> should be mentioned nearby, IMO.
------------------------------------------
On another note, this would seem to be a handy statement modifier
form for greppage:
my @threes = @list when $_ eq 3; # NOTE "where" sounds better
although appropriate aliasing syntax for this eludes me at the moment...
my @threes = $x <- @list when $x eq 3;
feels weird with the $x near the '='. And neither of these feels right
either:
my @threes = @list when -> $x { $x eq 3 }; # Close to A4 C<grep>
ayntax
my @threes = @list -> $x when $x eq 3; # Close to A4 C<for> syntax
Regards,
-- Gregor
