[antlr-interest] java example grammar

[ronald.petty at milliman.com]

I was trying to use the java grammar as a bases for a VB grammar (just 
seeing how to handle expression order etc).  The first structure I was 
trying to figure out for the for loop.  In the java.g there is

statement
        :
        ...
        // For statement
        |       "for"
                        LPAREN!
                                forInit SEMI!   // initializer
                                forCond SEMI!   // condition test
                                forIter         // updater
                        RPAREN!
                        statement                     // statement to loop 
over

        ....
        ;

If I was using this as the input

for ( i = 0; .......

It would match "for" "(" then call the rule forInit. 

forInit
                // if it looks like a declaration, it is
        :       (       (declaration)=> declaration
                // otherwise it could be an expression list...
                |       expressionList
                )?
                {#forInit = #(#[FOR_INIT,"FOR_INIT"],#forInit);}
        ;

I noticed that "i" cannot be a declaration because of the typeSpec in the 
declaration rule would mean it needs to "int i" or something like that, so 
I assume "i" is an expressionList (also because i had to be declared 
already).  So following that path lead to this

expressionList ->
expression->
assignmentExpression->
conditionalExpression->
logicalOrExpression->
logicalAndExpression->
inclusiveOrExpression->
exclusiveOrExpression->
andExpression->
equalityExpression->
relationalExpression->  (not 100% here)  (nested question; ( subrule1 )* | 
subrule2  if you don't match subrule1 do you have to match subrule2?  I 
think this does a zero match subrule1 here
shiftExpression->
additiveExpression->
multiplicativeExpression->
unaryExpression->
unaryExpressionNotPlusMinus->
postfixExpression->
primaryExpression->
identPrimary->
IDENT  (Match finally)

Hopefully I was right in this, if this is true, is this because 
        1) "i" is not a declaration (becuase in Java it has already been 
declared (and if Option Explicit is on in VB this is the same as having it 
Dim i somewhere or Public i)
        2) "i" is really an expression becuase it is really an LValue 
which is the output of someprevious RValue?  (I hope I am not slaughtering 
terms here)
        3) and becuase of 2) this means that an LValue is the simplest 
kind of expression and that is why it is at the end of this chain (meaning 
it is the highest on the precendence) (not sure about this)

I am thinking in the right way about this?

Thanks alot 
Ron

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