need urgent help with parser

im a beginner in PROLOG.i need urgent help with a simple prolog code.i need
to write a predicate parse/2 that would check the validity of an input
string against the given grammar.for eg.

?- parse(s, [a, b]).
Yes

should be the output.could any one let me know how to write the predicate
for this.

Thanks.

In message
< 09e77daf92c4fc32d1d852f4f31c72c1@localho
st.talkaboutprogramming.com>,
Pro_novice <cyb014@rediffmail.com> writes
>im a beginner in PROLOG.i need urgent help with a simple prolog code.i need
>to write a predicate parse/2 that would check the validity of an input
>string against the given grammar.for eg.
>
>?- parse(s, [a, b]).
>Yes
>
>should be the output.could any one let me know how to write the predicate
>for this.

I don't understand this.  For one thing, it sounds far too hard for a
beginner.  For another, you refer to "an input string" and "the given
grammar".  But in your sample call  parse(s, [a, b]),  there is no
string.  And is  [a, b]  in some way a grammar?

Nick
--
Nick Wedd    nick@maproom.co.uk