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Re: how should %^H work with lexical pramas

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From:
demerphq
Date:
March 29, 2006 02:59
Subject:
Re: how should %^H work with lexical pramas
Message ID:
9b18b3110603290258r72f78e8bx210a375954508264@mail.gmail.com
On 3/29/06, hv@crypt.org <hv@crypt.org> wrote:
> demerphq <demerphq@gmail.com> wrote:
> :On 3/28/06, Nicholas Clark <nick@ccl4.org> wrote:
> :> Logically, it seems, the way to go is to add something to make accesses of %^H
> :> at run time report the state of the compile time lexical pragmata. %^H should
> :> therefore be read only at runtime.
> :
> :Im a little confused about why %^H needs to be read only at run time.
>
> You snipped too much from Nick's email: immediately after the quoted para
> it says:
>
> :Except that this doesn't work. One scope's compile time is another scope's
> :runtime.

I snipped that because im talking about the case where the scopes run
time is not anyone elses compile time. Or at least that was my
thinking anyway...

> .. and later it continues:
>
> :I think there are actually two hashes, or things-with-a-hash-interface
> :that need to exist. A read only thing that reflects the hints in force
> :at the time of compilation of this statement, [and] a read/write thing
> :which reflects/affects the compilation of the immediate lexical caller,
> :if they are in compile time and we're in run time.
>
> The discussion is how to make accessible the first of these two hashes,
> without losing access to the second.

But again this discusess the case of  "if they are in compile time and
we're in run time"

Does the distinction between "somebody is in compile time" and "nobody
is in compile time" not matter for this conversation? I have to say
some of this discussion has gone over my head and I was just trying to
outline a use case that doesnt seem to match up. So if this is all
covered then fine.

Actually IMO thats a good point, this discussion is a lowlevel
discussion of how lexical pragmatta should work, but Im not sure that
ive seen a high level discussion of user defined lexical pragmatta
should work. In other words what are the use cases on user defined
lexical pragmatta? Once the use cases are clear wouldnt the low level
issues become a lot easier to address?

Anyway, maybe this is all clear from some doc or posting ive not seen,
if so could someone direct me to it?

Yves


--
perl -Mre=debug -e "/just|another|perl|hacker/"

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