1 files changed, 90 insertions, 0 deletions
diff --git a/tutorius/constraints.py b/tutorius/constraints.py
index cd71167..9ac1ca4 100644
--- a/tutorius/constraints.py
+++ b/tutorius/constraints.py
@@ -47,6 +47,96 @@ class Constraint():
         """
         raise NotImplementedError("Unable to validate a base Constraint")
     
+class TypeConstraintError(ConstraintException):
+    pass
+
+class TypeConstraint(Constraint):
+    """
+    Base class for ensuring that all the values have a specific Python type.
+    """
+    def __init__(self, expected_type):
+        """
+        Creates a new type constraint to restrict accepted values to a certain type.
+        @param expected_type A string describing the name of the type to enforce
+        """
+        self._expected_type = expected_type
+
+    def validate(self, value):
+        if self._expected_type == type(value).__name__:
+            return value
+        raise TypeConstraintError("Wrong type for value %s, got type %s; expected %s" % \
+                    (str(value),
+                     type(value).__name__,
+                     self._expected_type)) 
+
+class IntTypeConstraint(TypeConstraint):
+    """
+    Forces the value to be a Python int.
+    """
+    def __init__(self):
+        TypeConstraint.__init__(self, 'int')
+
+class FloatTypeConstraint(TypeConstraint):
+    """
+    Forces the value to be a Python float.
+    """
+    def __init__(self):
+        TypeConstraint.__init__(self, 'float')
+
+class StringTypeConstraint(TypeConstraint):
+    """
+    Forces the value to be a Python string.
+    """
+    def __init__(self):
+        TypeConstraint.__init__(self, 'str')
+
+class TupleTypeConstraint(TypeConstraint):
+    """
+    Forces the value to be a Python tuple.
+    """
+    def __init__(self):
+        TypeConstraint.__init__(self, 'tuple')
+
+class ListTypeConstraint(TypeConstraint):
+    """
+    Forces the value to be a Python list.
+    """
+    def __init__(self):
+        TypeConstraint.__init__(self, 'list')
+
+class BoolTypeConstraint(TypeConstraint):
+    def __init__(self):
+        TypeConstraint.__init__(self, 'bool')
+
+class MultiTypeConstraint(Constraint):
+    """
+    Base class for ensuring that all the values have a specific Python type.
+    """
+    def __init__(self, expected_types_list):
+        """
+        Creates a new type constraint to restrict accepted values to a certain type.
+        @param expected_types_list A list of strings describing the possible names 
+                                   of the types to enforce.
+        """
+        self._expected_types_list = expected_types_list
+
+    def validate(self, value):
+        if type(value).__name__ in self._expected_types_list:
+            return value
+        raise TypeConstraintError("Wrong type for value %s, got type %s; expected one in %s" % \
+                    (str(value),
+                     type(value).__name__,
+                     str(self._expected_types_list)))
+
+class ArrayTypeConstraint(MultiTypeConstraint):
+    """ Forces the value to either be a list or a tuple."""
+    def __init__(self):
+        MultiTypeConstraint.__init__(self, ['list', 'tuple'])
+
+class SequenceTypeConstraint(MultiTypeConstraint):
+    def __init__(self):
+        MultiTypeConstraint.__init__(self, ['list', 'tuple', 'str'])
+
 class ValueConstraint(Constraint):
     """
     A value constraint contains a _limit member that can be used in a children