prolog to solve grammar involving braces
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Abhilash Muthuraj
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Published on 2011-09-25T01:40:26Z
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2012/12/03
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I'm trying to solve DCG grammar in prolog and succeeded upto a point, i'm stuck in evaluating the expressions involving braces like these.
expr( T, [’(’, 5, +, 4, ’)’, *, 7], []),
expr(Z) --> num(Z).
expr(Z) --> num(X), [+], expr(Y), {Z is X+Y}.
expr(Z) --> num(X), [-], expr(Y), {Z is X-Y}.
expr(Z) --> num(X), [*], expr(Y), {Z is X*Y}.
num(D) --> [D], {number(D)}.
eval(L, V, []) :- expr(V, L, []).
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