6
我已經定義了以下函數用於beta測試,但我不確定如何考慮自由變量受限的情況。使用Haskell在lambda微積分中減少Beta測試
data Term = Variable Char | Lambda Char Term | Pair Term Term deriving (Show,Eq)
--substition
s[M:x]= if (s=x) then M else s
AB[M:x]= (A[M:x] B [x:M])
Lambda x B[M:x] = Lambda x B
Lambda y P[M:x]= if x=y then Lambda y P else Lambda y P (M:x)
--beta reduction
Reduce [s]= s
Reduce[Lambda x B]M = B[M:x]
Reduce[L1 L2] = (Reduce [L1] Reduce [L2])