From DGD Mailing List  Mon Dec 10 14:36:00 2001
From: DGD Mailing List (Felix A. Croes)
Date: Mon Dec 10 14:36:00 2001
Subject: [DGD] Re: Parse String and Virtual Objects

Par Winzell wrote:

>[...]
> The if if else ambiguity isn't so bad, but there are examples
> that get very bad very fast...
>
> ... and now after writing all this, I don't remember if DGD does
> or does not suffer a slow-down from an ambiguius grammar if it
> is called without its third argument (which specifies how many
> ambigously valid parse trees to return at each branch point).

parse_string() will always attempt all possible ambiguous parsings,
even if you do not instruct it to return more than one parse tree.
This is unlikely ever to be a problem with parsing player commands,
but it can be terrible when you try to parse a much longer string
with a grammar that contains a few innocent mistakes.

Regards,
Dworkin