aset/aref for char-tables, range-tables etc.

[Hrvoje Niksic]

Ben Wing <ben at xemacs.org> writes:

> well, but how do you think the extension from [] = array to [] = hash
> tables, etc. came about?  by the exact process of semantic extension.
> whether is what "there at the beginning of python" is irrelevant since
> python extended this notation from other languages,

That it was there at the beginning is exactly relevant to my point,
which is that Python *introduced* that notation from the start, it
didn't extend it from array access.  I agree that it is extended in
the sense that the operator was borrowed from other languages where it
denoted array access.  However, a syntactic shorthand is useful for
that kind of thing because it denotes a function without naming it
"array".  (Python does use names for its methods, and then it's called
get/set-item.)

I believe that "aref" stands for "array reference" and that the name
is a bad one outside the array context.  I don't have a really good
alternative name handy; maybe I would call it "item".  In that case it
should be setfable and support CL-style keyword arguments such as
:start and :end for slices.

>>>char tables are indexed by character and nothing else, but can take
>>>a charset or something similar as a shorthand for setting a value
>>>for all chars in the charset.  range tables are very similar but you
>>>can set ranges of integers instead of charsets.
>>
>>Then I wouldn't really say that they are good candidates for
>>aset/aref, in an "API design" sort of way.  But if you feel they're
>>good for compatibility, go ahead and put them in; I won't complain.
>>
>>
> what makes them not good?  the fact that they can take objects other
> than integers as set arguments?

The fact that they don't look up values using an integer index, the
way an array does.

> btw i semantically extended `get' from symbol properties to general
> properties, and you seemed to like it.

In that case the name `get' at least didn't imply a symbol argument.
On the other hand, `symbol-plist' does, which is why I assume
`object-plist' was introduced.