Re: Associative arrays and memory

[Sven Wischnowsky <wischnow@xxxxxxxxxxxxxxxxxxxxxxx>]

Peter Stephenson wrote:

> ...
>
> So, the question is are there any uses for special hashes which would
> require tying them directly to an internal variable or function, or
> can they always be accessed by the standard parameter functions?  I
> would think the whole point of using assoc arrays is to avoid any
> unpleasantness of the former kind.  Probably Sven can answer that
> better than anyone.

When thinking about using assoc. arrays for completion (and zle
widgets) I think of two uses: the one Bart mentioned in his reply
(`zle[...]') for access to various zle internals and one for the
mapping of command strings or environments to function( name)s which
produce the matches. The second one would be fully user-controlled (in 
the sense that the user might use it if (s)he wishes but the
completion code wouldn't enforce it). Hence this one would make no
trouble.
The first use might cause some trouble, you already described the
current use of LBUFFER and so on. For the completion stuff I'm not yet 
sure if we really need/should have settable parameters. If they are
settable it shouldn't be too hard to access their values via the
normal parameter interface (although making them special would
probably make things cleaner and easier to add the new things we may
one day find interesting).

So, I would like to reduce it to the question if we should use an
assoc array for the zle information or not. Using an assoc array only
for this may look a bit queer unless we use them in other places, too.
(Every time I think about this I can't help remembering the discussion 
about a new option system, am I the only one?)

Two more things about assoc arrays:

  typeset -A foo
  foo[hello]=world
  echo $foo[(i)w*]

gives `1', this should be `hello'.

And if we use an assoc array for completion command name patterns we
would need pattern matching the other way round: the keys are taken as 
patterns and `$funcs[(x)$cmdstr]' (for some value of `x') should give
the values of all entries whose key (taken as a pattern) match the
value of $cmdstr. But of course we could use a simple array for the
patterns and loop through it (the question is: are there other uses
where such a feature might be interesting to have, and: if we have a
way to get a list of matching entries, should we make this with a new
modifier flag that can be combined with `i', `I', `r', and `R' so that 
all of them give a list, not only the first matching one?).

Bye
 Sven


--
Sven Wischnowsky                         wischnow@xxxxxxxxxxxxxxxxxxxxxxx