feat(stream): adds filename

src/forthlift/forthlift.py

@@ -29,6 +29,18 @@ class stream:
         def __call__(self):
             return sys.stdin
 
+    class filename(Stream):
+        """Stream from the given file."""
+        def __init__(self, filename = ""):
+            self.filename = filename
+
+        def __call__(self):
+            self.fd = open(self.filename, 'r')
+            return self.fd
+
+        def __del__(self):
+            self.fd.close()
+
 class consume:
     class Consume:
         def __call__(self, stream):