On Sat, Jan 08, 2005 at 11:37:06AM -0700, Craig DeForest wrote:
: Is the perl6 expression : @a[4; 0..5]; : a 1x6 array (probably correct)? Or a 6 array (probably not correct)?
Certainly the former. I don't think dimensions should ever disappear accidentally.
Except when you assign in scalar context -- which I guess isn't accidental.
We know that
@a = (1, 2, 3); $b = @a[1];
Loses the dimension as a DWIM.
So perhaps we could say that assigning to a lower dimension always gets rid of a dimension of size 1 -- or error if it can't:
@c = ( 1,2,3 ; 4,5,6 ); @d[*;*] = @c[ 1 ; * ]; # @d is 2d @e[*] = @c[ 1 ; * ]; # @e is 1d @f = @c[1;1]; # @f is 2d: no dimensions lost
@g[*] = @c[ 0,1 ; 0,1 ]; # error: cannot collapse
as our disambiguator.
{ @c[;*] but shape(*) } wouldn't work, because the :shape option leaves additional dimensions open.
Dave.
