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Re: Working Group Proposal

From:
Nick Ing-Simmons
Date:
July 24, 2000 10:23
Subject:
Re: Working Group Proposal
Message ID:
200007241656.RAA18788@gabrielle.tiuk.ti.com
<abigail@foad.org> writes:
>
>I fail to see what LALR is going to gain us on the _P_erl level. 

What it means it you can tell what construct means by looking at next 'symbol'.
perl5 contorts itself to be able to use byacc (which is LALR(1)) by making 
deciding what the next 'symbol' is rather a complex process in toke.c.

As a result the 'grammar' in perly.y does not really describe perl5 that well.

So making perl6 LALR(1) "from the outset" would give "_P_erl" a more formal
definition.

>Sure,
>it might make _p_erl faster and leaner, 

Actually it probably would not make that much difference to '_p_erl'.

>but if we have to pay a price in
>Perl, is that worth it?
>
>> I would go even farther, and say that there should be three levels of LALR 
>> grammars - one for microperl, one for miniperl, and one for perl itself. 

I don't think so - the grammar just says what constructs are supported.
i.e. you can call subs - not which subs you can call. 
I don't think we want microperl to not have 'unless' if perl6 does.

-- 
Nick Ing-Simmons




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