[Grammatica-users] More JML Questions...

[Brandon Silverstein]

Per,

Thanks for your help so far.  I'm still having some trouble solving 
certain inherent ambiguities in my JML grammar.  For example, I rewrote 
the field declaration based on your suggestion from the first message I 
wrote:

field = DOC_COMMENT* modifiers* declaration
        | methodSpecification initOrStatement
        | "axiom" predicate ";"
        | ";";

declaration = memberDecl | jmlDeclaration;
initOrStatement = [ "static" ] compoundStatement | "static_initializer" 
| "initializer";

But Grammatica returns an error message stating:

Error: in jml.grammar: lines 538-541:
    inherent ambiguity in production 'field' starting with tokens
    "forall", "old", "requires", "pre", "requires_redundantly",
    "pre_redundantly", "diverges", "diverges_redundantly",
    "assignable", "assignable_redundantly", "modifiable",
    "modifiable_redundantly", "modifies", "modifies_redundantly",
    "when", "when_redundantly", "working_space",
    "working_space_redundantly", "duration", "duration_redundantly",
    "ensures", "post", "ensures_redundantly", "post_redundantly",
    "signals", "signals_redundantly", "exsures",
    "exsures_redundantly", "{|", "public", "protected", "private",
    "behavior", "exceptional_behavior", "normal_behavior",
    "model_program", "code_contract", "implies_that", "for_example",
    and "also"

Now this seemed strange to me because these tokens appear to be from 
the jmlKeyword prodcution, but not all of the tokens from the 
jmlKeyword list appear here.  Also, tokens like "{|" appear in the 
error message but this comes from a different production.  Does this 
have to do with the order in which my tokens are declared, or should 
these tags be parsed seperately like you state in your second reply?

Thanks for your help.

Brandon