[antlr-interest] Someting about range (to change)

[Fabien Hermenier]

Hi Bart

Here is. It's just a change in LEFTY:
---
fragment Digit :'0'..'9';
DEC_NUMBER: '1'..'9' Digit*;

fragment Letter    :'a'..'z'|'A'..'Z';

WS    :    ('\n'|'\r'|'\t'|' ') {$channel=HIDDEN;};
LEFTY: (Letter|Digit) ('.'|Letter|Digit|'-')* '[';
RIGHTY: ']' (('-' (Letter|Digit))|Letter|Digit)* ;

number :DEC_NUMBER;

range: LEFTY number '..' number RIGHTY;
---

Le 28/06/11 23:51, Bart Kiers a écrit :
> Hi Fabien,
>
> Can you post the grammar that produces the error?
>
> Bart.
>
>
> On Wed, Jun 29, 2011 at 5:57 AM, Fabien Hermenier 
> <hermenierfabien at gmail.com <mailto:hermenierfabien at gmail.com>> wrote:
>
>     Hi
>
>     I am sorry, but this is another problem related to sequence of
>     integer.
>     I don't understand my error(s), despite severals
>     pass on the wiki page related to this use case.
>
>     I want to parse a string with a "sequence" parameter into it, such as
>     "toto-[2 ..3]-toto".
>     Here is a short version of the grammar that works perfectly:
>     ---
>     grammar tryout;
>
>     options {
>         k=3;
>     }
>     fragment Digit :'0'..'9';
>     DEC_NUMBER: '1'..'9' Digit*;
>
>     fragment Letter    :'a'..'z'|'A'..'Z';
>
>     WS    :    ('\n'|'\r'|'\t'|' ') {$channel=HIDDEN;};
>     LEFTY: (Letter|Digit) (Letter|Digit|'-')* '[';
>     RIGHTY: ']' (('-' (Letter|Digit))|Letter|Digit)* ;
>
>
>     number :DEC_NUMBER; //HEX_NUMBER, OCT_NUMBER, ... are following but
>     removed for this example.
>
>     range: LEFTY number '..' number RIGHTY;
>     ---
>
>     This grammar accepts "toto-[1..3]-toto" or "toto-[1 .. 3]-toto".
>     Now, I want to be able to accept the LEFTY token or the RIGHTY token
>     even if they contains a '.' inside (not at the beginning). So I've
>     modified LEFTY as following:
>     LEFTY: (Letter|Digit) ('.'|Letter|Digit|'-')* '[';
>
>     Now, ANTLR does no longer accept "toto-[1..3]-toto". It requires at
>     least one space between the first number and the range.
>     I have read the wiki page related to range, integer, and so one.
>     But in
>     my case, I don't see where my grammar is ambiguous as no token
>     can start with a '.' . So it seems there is a concept I don't get. Can
>     anyone try to help me ?
>
>     Thanks in advance,
>     Fabien.
>
>     List: http://www.antlr.org/mailman/listinfo/antlr-interest
>     Unsubscribe:
>     http://www.antlr.org/mailman/options/antlr-interest/your-email-address
>
>


-- 
postdoctoral researcher at Flux
School of Computing, University of Utah
http://sites.google.com/site/hermenierfabien/home