Re: LL(1) vs LALR(1) parsers

> Why do compiler design text book authors only describe recursive parsers
> as a step stone on their way to bottom up parsers? I know that LALR allows
> for more complex grammars, but many languages can be described by LL(1)
> grammars. If LL(1) can yield faster, smaller and more understandable
> parsers with better error handling for many languages, why isn't this
> method more elaborated? (Holub, as an example, presents full grammar and
> compiler listings for a bottom-up C-compiler, not for top-down).


Intellectual bigotry!!!!!


That is, the automated parsers use a great deal of automata theory
which helps build on the computer science foundation. Recursive descent
parsers are a small matter of programming (SMOP). I do notice among
peers in industry that people are no longer snubbing the idea of writing
a recursive parser when it is appropiate.


Remember you don't take a compiler course to learn how to build a
compiler, surprise... Most people never write a compiler. You take
it for the following reasons:


- Improving your comp. sci. background to understand
automata theory with a very good application.
- Understanding what a compiler may do (or not do) for
your code.
- Learning about big system software, data structures, etc.


Thank you.


Steve Simmons
[I agree that few CS students will write a conventional compiler, but we all
end up having to decode some sort of input language in an application. -John]


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