two versions of semantics (the Logic version incomplete)

examples/tutorial/semantics/AnswerBase.hs

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+module AnswerBase where
+
+import GSyntax
+
+-- interpretation of Base
+
+type Prop = Bool
+type Exp = Int
+domain = [0 .. 100]
+
+iS :: GS -> Prop
+iS s = case s of
+  GPredAP np ap -> iNP np (iAP ap)
+  GConjS c s t  -> iConj c (iS s) (iS t)
+
+iNP :: GNP -> (Exp -> Prop) -> Prop
+iNP np p = case np of
+  GEvery cn -> all (\x -> not (iCN cn x) || p x) domain
+  GSome  cn -> any (\x ->      iCN cn x  && p x) domain
+  GConjNP c np1 np2 -> iConj c (iNP np1 p) (iNP np2 p)
+  GUseInt (GInt i) -> p (fromInteger i)
+
+iAP :: GAP -> Exp -> Prop
+iAP ap e = case ap of
+  GComplA2 a2 np    -> iNP np (iA2 a2 e)
+  GConjAP c ap1 ap2 -> iConj c (iAP ap1 e) (iAP ap2 e)
+  GEven -> even e
+  GOdd -> not (even e)
+
+iCN :: GCN -> Exp -> Prop
+iCN cn e = case cn of
+  GModCN ap cn0 -> (iCN cn0 e) && (iAP ap e)
+  GNumber -> True
+
+iConj :: GConj -> Prop -> Prop -> Prop
+iConj c = case c of
+  GAnd -> (&&)
+  GOr  -> (||)
+
+iA2 :: GA2 -> Exp -> Exp -> Prop
+iA2 a2 e1 e2 = case a2 of
+  GGreater -> e1 > e1
+  GSmaller -> e1 < e2 
+  GEqual   -> e1 == e2