> But is it OK for a list to be silently promoted to an array when used
> as an array? So that all of the following would work, and not just 50%
> of them?
> (1..10).map {...}
> [1..10].map {...}
And somehow related to all this . . .
Let's assume for the moment that there's still a functional version of
the C<map> operator (I think Larry indicated that it probably wouldn't
be going away, despite <~ and friends). I'm also going to use $_ in the
code block, even though things like $^a exist. Lowest common
denominator and all that.
Let's also assume:
@count = (1, 2, 3, 4, 5);
@smallcount = (2, 3, 4);
$#array works like in Perl5 (if not, you can mentally change my
notation below)
What's the result of these statements in Perl6?
@a = map { $_ + 1 } @count; # my guess: @a = (2, 3, 4, 5, 6)
@a = map { $_ + 1 } @count[0..$#count]; # my guess: @a = (2, 3, 4, 5, 6)
@a = map { $_ + 1 } (1, 2, 3, 4, 5); # my guess: @a = (2, 3, 4, 5, 6)
All fair enough. Now how about these?
@a = map { $_ + 1 } (1, @smallcount, 5); # Three or five elements?
@a = map { $_ + 1 } (1, @smallcount[0..$#smallcount], 5); # Array slices appear to
be lists
@a = map { $_ + 1 } \@count; # Map the array or its reference?
@a = map { $_ + 1 } [1, 2, 3, 4, 5]; # one-element list or five-element array?
$ref = @count;
@a = map { $_ + 1 } $ref; # Map the scalar or the array it refers to?
@a = map { $_ + 1 } @count; # Am I sure about this one any more, given the one
above?
There's a slippery slope here that needs propping up.
It's things like this that make me worry a great deal about implicit
dereferencing, something which is going to be happening a lot more in
Perl6 than in Perl5.
Where's the list of rules that state:
- when implicit referencing happens
- when implicit dereferencing happens
- when arrays are flattened into lists, and
- how to stop this from being the default, and
- how to make it happen when it isn't the default
- how arrays of pairs, lists of pairs (i.e., "hash literals")
and hashes are related, and when one can be substituted for
another (and when one is implicitly converted to another)
?
I think some of this is in A2, but not all of it.
I'm prepared to summarize the outcome of this discussion if we actually
arrive at anything definite.
--
Debbie Pickett http://www.csse.monash.edu.au/~debbiep [EMAIL PROTECTED]
"Oh, she's got it bad." "What? What has she got?" "Isn't it obvious, Daddy?
Ariel's in *love*." - _The Little Mermaid_
