[antlr-interest] Check for end of token stream when parser finishes.

[Gyanit Singh]

The problem still remains.
----------------------
grammar test;
test     : (exp EOF)+;
exp    : ONE ('+' ONE)* ;
ONE    : '1';
EOF   : ';'
-----------------------

Now I am looking for list of expression seperated by a semicolon. The
problem is checking whether parser have matched the whole token stream or
not.

Now "1+1;11+1;" will match "1+1;" and ignores last "11+1;". The application
requires me of raising an exception whenever there are tokens remaining (as
it is more likely input error).

-gyanit

Hi,You could use the EOF token to match the whole input
> test: exp EOF;
> -shibin
>
>
> On Tue, Jun 30, 2009 at 5:29 AM, Gyanit Singh <gyanit at gmail.com> wrote:
>
>> Hi all,
>>
>> I have a simple grammar
>> ----------------------
>> grammar test;
>> test     : exp;
>> exp    : ONE ('+' ONE)* ;
>> ONE    : '1';
>> -----------------------
>>
>> if you try to parse "1+11" the parser matches test and expr to "1+1" and
>> ignores the last "1". Is there a way to throw an exception when this
>> happens.
>>
>> More abstractly, when the rule is kleene closure (or plus) and it ends
>> leading to the end of the main rule (for the above example rule "test") and
>> still there are tokens remaining then how to throw and exception instead of
>> partial match. In other words, after the parsing is done how to check
>> whether the token stream has ended or not?
>>
>> thanks,
>> gyanit.
>>
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>
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