[antlr-interest] adding node to AST

[Bryan Ewbank]

Hi Donal,

Since you're calling it a *token* rather than a sequence of tokens, it
seems you should be gathering these in the lexer - or is arbitrary
whitespace between the elements allowed, like this:
               SubscriptionManager
               :                            2345
               { }

... ... ...
Assuming that this is a *token*, rather than a sequence of tokens,
something like the following will work:

    // somewhat abstract lex syntax; sorry...
    SubscriptionManager:[0-9][0-9]*     { return SUBSCRIPTION_MANAGER; }

This way, every token that starts with SubscriptionManager: and has a
trailing integer component will be folded into one abstract token, and
allows your grammar to look like this:

    subscriptionManager!
        x:SUBSCRIPTION_MANAGER^ LBRACE! (subscriptionLevel)* RBRACE!
        | "SubscriptionManager"
            {
                // choke and die here!;
            }
    ;

This results in a parent node of SUBSCRIPTION_MANAGER, containing the
appropriate string, and the trees produced by the <subscriptionLevel>
elements are the children:
    [SUBSCRIPTION_MANAGER,"SubscriptionManager:01"]
        [SUBSCRIPTION_LEVEL, ... ]
        [SUBSCRIPTION_LEVEL, ... ]
        [SUBSCRIPTION_LEVEL, ... ]


Hope this helps,
- Bryan Ewbank