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Re: Working Group Proposal

Nick Ing-Simmons
July 24, 2000 13:33
Re: Working Group Proposal
Message ID:
<> writes:
>On Mon, Jul 24, 2000 at 05:56:56PM +0100, Nick Ing-Simmons wrote:
>> <> 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.
>Well, yes, I know what LALR parsing is.

Fair enough but I thought it was worth spelling out for those that might not.

>> 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.
>But from the point of view of the language user, the Perl programmer, what
>will the gain be? What will the *loss* be?

An LALR(1) grammar is likely to seem more "consistent", and as I said above
you will have BNF-like grammar that formally defines what is legal - some
people may like that.

But I don't think that Perl programmers are the main beneficiaries of the
change - rather it is those of "us" that have to maintain the front end
have something that is less fragile.

Nick Ing-Simmons Perl Programming lists via nntp and http.
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