fromstring.py weg, fromstring met Var+Abst in main

main.py

-
-
 class LambdaTerm:
     """Abstract Base Class for lambda terms."""
 
     def fromstring(self):
         """Construct a lambda term from a string."""
-        raise NotImplementedError
+        if "." in self:
+            return Abstraction.fromstring(self)
+        else:
+            return Variable(self)
 
     def substitute(self, rules):
         """Substitute values for keys where they occur."""
@@ -32,6 +33,9 @@ class Variable(LambdaTerm):
         newsymbol = rules
         return Variable(newsymbol)
 
+    def fromstring(self):
+        return eval(f"Variable('{self}')")
+
 
 class Abstraction(LambdaTerm):
     """Represents a lambda term of the form (λx.M)."""
@@ -44,14 +48,22 @@ class Abstraction(LambdaTerm):
         return f"Abstraction({repr(self.var)}, {repr(self.body)})"
 
     def __str__(self): 
-        return f"λ{self.var}.{self.body}"
+        return f"λ{self.var}. {self.body}"
 
     def __call__(self, argument): raise NotImplementedError
 
     def substitute(self, rules):
-        newbody = Variable(str(self.body).replace(str(self.var), str(rules)))
+        newbody = LambdaTerm.fromstring(str(self.body).replace(str(self.var), str(rules)))
         return newbody
 
+    def fromstring(self):
+        lijst = self.split(". ")
+        if len(lijst[0]) > 2:
+            return Abstraction(Variable.fromstring(lijst[0][1]), Abstraction.fromstring(self[2:]))
+        else:
+            newvar = Variable.fromstring(lijst[0][1])
+            newbody = Variable.fromstring(lijst[1])
+        return Abstraction(newvar, newbody)
 
 class Application(LambdaTerm):
     """Represents a lambda term of the form (M N)."""
@@ -74,10 +86,10 @@ class Application(LambdaTerm):
         ans = self.function.substitute(self.arg)
         return ans
 
-x = Variable('x')
-a = Variable('a')
-id = Abstraction(x, Variable('x x'))
-id_x = Application(id, Abstraction(a, a))
-red = id_x.reduce()
+    def fromstring(self):
+        raise NotImplementedError
+
+
 
-print(id_x, "-->", red, "-->", type(red))
\ No newline at end of file
+print(str(LambdaTerm.fromstring(r"\a b. a")))
+print(type(LambdaTerm.fromstring(r"\a b. a")))
\ No newline at end of file