[antlr-interest] Perority Enforcing using Antlr Grammar

[Muhammad Masoom Alam]

Hi all,

Precisely the question is that i have some oridnary
boolean expressions. like 

BooleanExp:  Predicate ((AND|OR) Predicate)*
          ;

This predicate is any boolean expression as we have in
java or C++, but how to mark the perority here. i mean
i can have a predicate expression of the form:
  (a=2) and (c<3 or d>4)

How to make these preferecnes implementable i.e. if
there is a start paranthesis, there should be an end
parantheisis and there can be more paranthesis within
predicates. If i make the grammar of the form:

BooleanExp: (LPAREN|Empty) Predicate (RPAREN|Empty)
((AND|OR) Predicate)*
          ;

This is logically not correct, since start can be
empty and end can be a paranthesis, which is really
not the required result!

Thanks
MA

 
--- Muhammad Masoom Alam <doublemalam at yahoo.co.uk>
wrote:

> Hi all,
> 
>  sorry if my question is a stupid one, as i am a new
> bie. How to enforce perority rules using Antlr.
> 
> e.g. I have the following conditions
> 
>   (Predicate1 And (Predicate2 Or Predicate3))
> 
> In the above, Grammar, paranthesis are used to group
> and enforce perority, but how this will be done
> using
> the Antlr Grammar.
> 
> Thanks in Advance.
> MA
> 

> 
> 
> 		
>
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