Re: grammar for propositional logic

[Martin McDermott]

Your right, I undid one to many lines and killed it... Sorry about that.

At first I thought I understood the error, I thought it was a problem when
you have cases like 3 variables but 2 operations. The easier 2 variables and
1 op also fails, so now i"m not sure what its telling me. The output is
below.

Thanks again guys

--(end of buffer or a NUL)
--accepting rule at line 33 ("p")
--accepting rule at line 36 (" ")
--accepting rule at line 25 ("OR")
--accepting rule at line 36 (" ")
--accepting rule at line 33 ("q")
--accepting rule at line 36 (" ")
--accepting rule at line 25 ("OR")
--accepting rule at line 36 (" ")
--accepting rule at line 33 ("r")
--accepting rule at line 37 ("
")

--accepting rule at line 33 ("p")
--accepting rule at line 36 (" ")
--accepting rule at line 22 ("AND")
--accepting rule at line 36 (" ")
--accepting rule at line 33 ("q")
--accepting rule at line 37 ("
")

--accepting rule at line 28 ("NOT")
--accepting rule at line 36 (" ")
--accepting rule at line 33 ("r")
--accepting rule at line 37 ("
")

--(end of buffer or a NUL)
--EOF (start condition 0)
syntax error, unexpected $end, expecting T_TRUE or T_FALSE or T_NOT or
T_VARIABLE


On Wed, Sep 1, 2010 at 4:01 AM, John P. Hartmann <address@hidden>wrote:

> You didn't turn on debugging in flex, which is why it doesn't tell you
> anything.
>
> Assuming you don't care about whitespace, you need to split the rule
> on line 39 into
>
> [ \t\r]               ;
> [\n]                 {lexEcho("%s", yytext); return yytext[0];}
>
> The default rule needs to return something or abort the parse.  You
> might return T_ERROR in case you'd like to find more than one error a
> throw.
>
>   j.
>
> On 1 September 2010 09:43, Martin McDermott
> <address@hidden> wrote:
> > Flex doesn't give me any output and looking online it looks like
> whitespace
> > wouldn't be causing this. For everything else I used the "." to have misc
> > things printed out.
> >
> > So I'm not sure how thats possible or where its coming from. I attached
> the
> > file in case anyone feels like taking a look.
> >
>