Re: LALR Grammar help

[Hans Aberg]

On 23 Aug 2005, at 23:32, Michael Schidlowsky wrote:

> I am working on a LALR grammar and am relatively knew to the craft of
> writing LALR grammars.  The grammar is for a procedural style
> programming language that looks like java, and includes an additional
> block appended to the text which is where the program should start  
> (the
> equivalent of a main method, but outside the class).
>
> I'm including the grammar file below.  I'd appreciate help in two  
> areas:
>
> 1. How can I include support for procedure calls in addition to  
> function
> calls?  Right now CUP generates a parser that recognizes
>
> a = myclass.fun(b);
>
> but not
>
> myclass.fun(b);

There is a Yacc-grammar for C++:
  http://www.parashift.com/c++-faq-lite/compiler- 
dependencies.html#faq-38.11
You might check how it is resolved there.

> 2. Are there any parts of the grammar that those of you with more
> experience would recommend that I do differently?  I'm not only
> interested in getting this to work properly, but in the craft of  
> grammar
> writing in general, and in making this as clear as possible to the  
> user
> or the grammar.

Fewer rules makes a more comprehensible grammar. Sometimes token  
precedences can be used.

  Hans Aberg