Re: [Toss-devel] Specification of Hierarchical Terms

[Lukasz S. <luk...@gm...>]

On Sun, Jul 1, 2012 at 5:39 AM, Lukasz Stafiniak <luk...@gm...> wrote:
> On Sun, Jul 1, 2012 at 5:07 AM, Lukasz Kaiser <luk...@gm...> wrote:
>>
>> Hmm - we currently enforce all our rules to be left-linear.
>> Maybe we could handle the linear case first, and then
>> join the non-linear case with sharing in the next step?
>> (I know parsing must handle right sides as well, this is just a hope.)

The move to left-linear rules is nice in that after introducing
sharing (according to the proposal), the semantics of non-linear rules
change: sharing in pattern requires sharing in matched (sub)term.

> I've solved it (I'm still writing down the details, I'll post the
> updated specs again). I've strayed away from the definition of "Typed
> Feature Structures" unnecessarily worrying of introducing sharing too
> early, but I can treat identity that later will be sharing as
> (syntactic) equality for now.