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Postings from October 2002
On Fri, 11 Oct 2002, Jonathan Scott Duff wrote:
: On Fri, Oct 11, 2002 at 03:21:38PM +0100, Aaron Crane wrote:
: > Vaguely heretical, I know, but I'd be inclined to do something like this:
: >
: > Perl 5 Proposed Perl 6
: > $x && $y $x & $y
: > $x || $y $x | $y
:
: Larry just added nice character doubling ops to be more consistent and
: here you want to take two of them away? :-)
I doubt I'd muck with the doubled ones.
I'm wondering whether the single ones could indicate parallel streams.
We had the difficulty of specifying whether the C<for> loop should
terminate on the shorter or the longer stream. We could say that |
terminates on the longer, and & on the shorter. Possibly there's
some relationship with any() and all() in there as well. The | could
generally be construed as a comma that doesn't guarantee ordering.
So cases could be written
when 1 | 2 | 3 {...}
as well as with comma. Saying
when 1 & 2 & 3 {...}
might be short for
when all(1,2,3) {...}
: > $x & $y bitand($x, $y)
: > $x | $y bitor($x, $y)
: >
: > Using functions instead of operators for these operations seems reasonable
: > to me given how often they're useful.
:
: How about these?
:
: $x band $y
: $x bor $y
:
: Of course, then people will probably expect these too:
:
: $x bshl $y
: $x bshr $y
: $x bxor $y
:
: Hrm ...
:
: sysopen(FOO,"foo", O_WRONLY bor O_CREAT bor O_TEXT)
: sysopen(FOO,"foo", bor O_WRONLY, O_CREAT, O_TEXT)
:
: :-(
:
: As long as we're in fantasy-land, how about these?
:
: $x .& $y
: $x .| $y
I was thinking more along the lines of:
$x &&& $y
$x ||| $y
But then there's ~ vs ~~~ too. The triple syntax at least has the
virtue of the visual metaphor of doing a bunch of ANDs or ORs in
parallel. But it's kind of odd to write ~~~$x for a one's complement.
Anyone else want to be UNSUBSCRIBED IMMEDIATELY? :-)
: Those look like bit operations to me :-)
:
: > I'm not especially fond of the names bitand and bitor, but they're
: > accurate, reasonably short, and have prior art in C and C++.
:
: Not all prior art is necessarily good art :-)
:
: > Two things about this proposal:
: >
: > * This leaves && and || available for other purposes, but I can't
: > off the top of my head think of anything else I'd want them for.
:
: Then why muck with them? Just munge the bitwise operators.
:
: > * Does this make it harder to write overloaded bitwise ops for your
: > classes?
:
: No harder than it was before especially given that you can warp the
: syntax however you please.
No warpage necessary. All operators can be named as functions with
operator: on the front.
Larry