> -----Original Message-----
> From: Damian Conway [mailto:[EMAIL PROTECTED]
> Sent: Wednesday, 10 March, 2004 09:48 PM
> To: [EMAIL PROTECTED]
> Subject: Re: Mutating methods
>
>
> Brent "Dax" Royal-Gordon wrote:
>
> >> / $foo:=(abc) $bar:=(def) /
> >
> > Am I misreading, or are you suggesting that $foo may contain
> 'abc' after
> > running this example, even if the match wasn't successful?
>
> No. I re-checked with Larry this morning and he confirmed that
> all bindings in
> rules only "stick" if the rule as a whole succeeds.
>
> What I was trying (obviously rather ineptly ;-) to point out is
> that we have
> to be able to differentiate between the the match object's own internal
> hypothetical variables ($?foo, $?bar, @?baz) and any
> external-but-temporarily-hypothesized variables ($foo, $bar, @baz).
>
> The syntax we've chosen to do that requires the use of "?" as a secondary
> sigil on internal variables. So, since named subrules that capture always
> capture to internal variables, it's natural and consistent to use "?" to
> indicate capturing subrules as well.
Isn't this backwards?
That is, from the above I get the impression that $?foo is TRANSIENT, while
capturing to $foo will (eventually) be PERMANENT.
So <?foo> is just a shorthand way of saying
$?foo := <foo>
right?
Is hypo-space a flat entity, or do hypothetical scopes nest? If so, do we
have to use repeated ?'s, or will just one suffice?
That is:
rule bar {...}
rule baz {...}
rule foo {...bar...baz...}
if / <?foo> ... <?baz> ... { $?foo.?baz ... $?baz } .../
OR
if / <?foo> ... <?baz> ... { $?foo.baz ... $?baz } .../
OR
if / <?foo> ... <?baz> ... { $?baz ... $?otherbaz } .../
=Austin
