Front page | perl.perl6.language.data |
Postings from September 2000
> This RFC proposes that operators in a list context should be applied > element-wise to the elements of their arguments: > > @d = @b * @c; # Returns (2,8,18) > > If the lists are not of equal length, an error is raised. I've been watching this RFC for a while. I would hesitate to change the default behavior of * and other operators in so radical a sense, especially since it would create unexpected error conditions. I think these operations should remain scalar. However, we need a means to do what you're after, definitely. I would recommend you check out RFC 200, just posted, which proposes massive tie changes that would allow for integrated data, function, and operator overloading. From the RFC: tie My::Matrix @a; # tie @a to $obj @c = @a + @b; # @c = $obj->ADD(@b); $a[0] = 4; # $obj->STORE(0, 4); @d = @a * @b; # @d = $obj->MUL(@b); The idea would be operator and data overloading is completely integrated with tie, based on the concept of polymorphic objects. As such, you could create native PDL classes that would allow @a * @b to do what you want. Otherwise, you have to decide if @a * @b should be element-wise, a cross-product, a vector, or ??? I just think it's a can of worms that's going to result in a set of arbitrary decisions, which in the the end makes less sense than having these contexts remain scalar by default. -NateThread Previous | Thread Next