Start of binary expressions

Author: Bruce Fenske

Diff for: py_queryable/expressions/binary.py

@@ -1,23 +1,43 @@
+import abc
 from . import Expression
 
 
 class BinaryExpression(Expression):
-    def __init__(self, left_exp, op_exp, right_exp):
+    def __init__(self, left_exp, right_exp):
         super(BinaryExpression, self).__init__()
         self.left = left_exp
-        self.op = op_exp
         self.right = right_exp
 
+    @abc.abstractmethod
     def visit(self, visitor):
-        return visitor.visit_BinaryExpression(self)
+        raise NotImplementedError()
 
     @property
     def children(self):
-        return [self.left, self.op, self.right]
+        return [self.left, self.right]
 
     def __repr__(self):
-        return u"{0}(left={1}, op={2}, right={3})".format(
+        return u"{0}(left={1}, right={3})".format(
             self.__class__.__name__,
             self.left.__repr__(),
-            self.op.__repr__(),
             self.right.__repr__())
+
+
+class JoinExpression(BinaryExpression):
+    def __init__(self, outer_exp, inner_exp, outer_key, inner_key, select_func):
+        super(JoinExpression, self).__init__(outer_exp, inner_exp)
+        self.inner_key = inner_key
+        self.outer_key = outer_key
+        self.select_func = select_func
+
+    def visit(self, visitor):
+        return visitor.visit_JoinExpression(self)
+
+    def __repr__(self):
+        return u"JoinExpression(outer={0}, inner={1}, outer_key={2}, inner_key={3}, select={4})".format(
+            self.left.__repr__(),
+            self.right.__repr__(),
+            self.outer_key.__repr__(),
+            self.inner_key.__repr__(),
+            self.select_func.__repr__()
+        )

Diff for: py_queryable/visitors/sql.py

@@ -132,3 +132,6 @@ def visit_SumOperator(self, expression):
 
     def visit_AveOperator(self, expression):
         return self._visit_lambda(expression, u"AVG")
+
+    def visit_JoinExpression(self, expression):
+        raise NotImplementedError()