Merge 46f3305 into 2ad07ff

hwtypes/adt.py

@@ -1,4 +1,5 @@
 from .adt_meta import TupleMeta, ProductMeta, SumMeta, EnumMeta, is_adt_type
+from collections import OrderedDict
 from types import MappingProxyType
 
 __all__  = ['Tuple', 'Product', 'Sum', 'Enum']
@@ -80,7 +81,7 @@ def __repr__(self):
 
     @property
     def value_dict(self):
-        d = {}
+        d = OrderedDict()
         for k in type(self).field_dict:
             d[k] = getattr(self, k)
         return MappingProxyType(d)

hwtypes/adt_meta.py

@@ -1,6 +1,7 @@
 import itertools as it
 import typing as tp
 from abc import ABCMeta, abstractmethod
+from collections import OrderedDict
 
 import weakref
 
@@ -190,7 +191,7 @@ def from_fields(mcs, fields, name, bases, ns, **kwargs):
         if '_field_table_' in ns:
             raise ReservedNameError('class attribute _field_table_ is reserved by the type machinery')
         else:
-            ns['_field_table_'] = dict()
+            ns['_field_table_'] = OrderedDict()
 
         def _get_tuple_base(bases):
             for base in bases:

tests/test_adt.py

@@ -15,6 +15,14 @@ class Pr(Product):
     x = En1
     y = En2
 
+class Pr2(Product):
+    x = En1
+    y = En2
+
+class Pr3(Product):
+    y = En2
+    x = En1
+
 Su = Sum[En1, Pr]
 
 Tu = Tuple[En1, En2]
@@ -106,6 +114,10 @@ def test_product():
     with pytest.raises(TypeError):
         p[0] = En2.c
 
+    assert Pr != Pr2
+    assert Pr.field_dict == Pr2.field_dict
+    assert Pr.field_dict != Pr3.field_dict
+
 
 def test_sum():
     assert set(Su.enumerate()) == {