1 files changed, 25 insertions, 0 deletions
diff --git a/lib/sly/ast.py b/lib/sly/ast.py
new file mode 100644
index 0000000..7b79ac5
--- /dev/null
+++ b/lib/sly/ast.py
@@ -0,0 +1,25 @@
+# sly/ast.py
+import sys
+
+class AST(object):
+    
+    @classmethod
+    def __init_subclass__(cls, **kwargs):
+        mod = sys.modules[cls.__module__]
+        if not hasattr(cls, '__annotations__'):
+            return
+
+        hints = list(cls.__annotations__.items())
+
+        def __init__(self, *args, **kwargs):
+            if len(hints) != len(args):
+                raise TypeError(f'Expected {len(hints)} arguments')
+            for arg, (name, val) in zip(args, hints):
+                if isinstance(val, str):
+                    val = getattr(mod, val)
+                if not isinstance(arg, val):
+                    raise TypeError(f'{name} argument must be {val}')
+                setattr(self, name, arg)
+
+        cls.__init__ = __init__
+