[antlr-interest] Problems with the ANTLRworks interpreter.

[rkevinburton at charter.net]

I don't know if this will help but I have found that the output changes based on the line ending selected (Unix(LF) or MS(CR LF).

Kevin

---- "Peter C. Chapin" <pcc482719 at gmail.com> wrote: 
> Hello!
> 
> I'm using ANTLRworks 1.1.7 and I'm building a grammar for a C-like 
> language. I've created some unit tests for my grammar... specifically a 
> collection of files containing text that is intended to be syntactically 
> correct. My test program loops over these files, instantiates a parser 
> for each (one at a time), and tries to parse them all. I use various 
> start symbols to exercise parts of the grammar incrementally in these 
> tests (helps to isolate errors).
> 
> So, given a file containing just
> 
> A = B
> 
> my test program successfully parses this using a start symbol of 
> 'expresion.' This is fine. However, when I use the ANTLRworks 
> interpreter and enter the text 'A = B' I get a 'NoViableAltException.' I 
> noticed that the interpreter is ignoring my WHITSPACE rule so I removed 
> the white space from the text (using 'A=B') but that didn't help. In 
> fact, the interpreter produces a NoViableAltException even when I just 
> use 'A' as input text. However, a bare identifier is a valid expression 
> in my target language (and it parses fine when using the test program I 
> described above).
> 
> I'm think I am missing something fundamental about how the interpreter 
> is supposed to work. I'm hoping someone can set my feet upon the path of 
> enlightenment! I did check the on-line ANTLRworks user's guide, but the 
> section on the interpreter doesn't shed much light on my question.
> 
> P.S. I do have backtracking mode turned on right now in my grammar's 
> option. Could that have something to do with it?
> 
> Peter
>