[antlr-interest] Changing/affecting the Lexer from the Parser?

[Bernard Kaiflin]

Ola,

It seems you are in charge of the grammar. So I suppose that there is no
FLOAT rule and you have INT DOT INT each time there is `1.2`in the input.
Taken at the beginning of the thread, your requirements are

ARR(1:5)
ARR(1.2:4)
ARR(1.#I:#J)
ARR(#I.2:4), in which .2 is a valid floating point number, but 1. isn't.

I don't understand .2 as float as start position. Without a description of
the specifications and the purpose of the notation, it's hard to help you.
If I call index the digit/variable before the dot, a full description of
array could be :

array : 'ARR' '(' index? dimension ')' ;
index : d_v '.' ;
d_v   : DIGIT | variable ;
variable : '#' ID ;
dimension : d_v ':' d_v ;

HTH
Bernard


2012/11/10 Juancarlo Añez <apalala at gmail.com>

> Bernard,
>
> On Sat, Nov 10, 2012 at 4:35 PM, Bernard Kaiflin <bkaiflin.ruby at gmail.com
> >wrote:
>
> > to match the pre-generated token stream and programmatically split
> > $FLOAT.text into two parts : index and start (dimension).
>
>
> That patch is also an option I had thought of before, but it's an ugly
> patch.
>
> I also have to deal with #I.2 and 1.#X, and #X.#Z, which are currently
> dealt with by making ID consume both sides of the dot, just for parsing's
> sake.
>
> -- Juanca
>
>
>
> --
> Juancarlo *Añez*
>
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