As I said, I am speaking only of semantics, not implementation details.
On Fri, 17 Jun 2022, Henry Rich wrote:
u&.> Is backed by special code that avoids explicit boxing and unboxing.
And, if the contents of the boxes are inplaceable, u is executed inplace.
Henry Rich
On Fri, Jun 17, 2022, 1:39 AM Elijah Stone <elro...@elronnd.net> wrote:
On Thu, 16 Jun 2022, Marshall Lochbaum wrote:
> You seem to think building these out of boxes makes some philosophical
> difference. I disagree. Boxes are used to implement array nesting.
I do think it makes a difference. But there is also a practical question:
what patterns does the language encourage?
It is possible to go even further: boxes do not need to be in the language
at
all, as they can be implemented in userspace (albeit not in a modular
fashion).
> No. The marker can be derived as part of the previous operation (*&.>),
so
> making it part of the next one duplicates information.
*&.> is two operations: multiplying, and boxing. (Actually it's three,
since
it also unboxes, or really four, since it requires that the right argument
be
pre-boxed.) */, or *"_1 _ (same thing) is only one
operation--multiplication--with the rank specifying how the multiplication
is
to be performed (or two, if you consider rank to be an operation unto
itself).
No information is duplicated, then, because, as the result is a flat array
rather than a boxed array, there are multiple ways of joining it. (This
is
also clearly more suggestive.)
With nests, the operations are:
- enclose
- multiply each
- join
with boxes, and a requisite 'join', the operations are:
- multiply at rank
- join selected axes
The rank and axis specifications of the latter form speak to its
generality.
-E
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