From 7f8be591111d9fda9fb52fe1896c8c14f077a9a5 Mon Sep 17 00:00:00 2001
From: Damien George <damien.p.george@gmail.com>
Date: Thu, 20 Mar 2014 19:20:59 +0000
Subject: [PATCH] py: Allow hashing of functions and tuples.

---
 py/obj.c      | 11 +++++++++--
 py/obj.h      |  1 +
 py/objtuple.c | 11 +++++++++++
 3 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/py/obj.c b/py/obj.c
index e98dbae6cf..0c91e8f6d8 100644
--- a/py/obj.c
+++ b/py/obj.c
@@ -81,9 +81,16 @@ machine_int_t mp_obj_hash(mp_obj_t o_in) {
         return mp_obj_str_get_hash(o_in);
     } else if (MP_OBJ_IS_TYPE(o_in, &none_type)) {
         return (machine_int_t)o_in;
+    } else if (MP_OBJ_IS_TYPE(o_in, &fun_native_type) || MP_OBJ_IS_TYPE(o_in, &fun_bc_type)) {
+        return (machine_int_t)o_in;
+    } else if (MP_OBJ_IS_TYPE(o_in, &tuple_type)) {
+        return mp_obj_tuple_hash(o_in);
+
+    // TODO hash class and instances
+    // TODO delegate to __hash__ method if it exists
+
     } else {
-        assert(0);
-        return 0;
+        nlr_jump(mp_obj_new_exception_msg_varg(&mp_type_TypeError, "unhashable type: '%s'", mp_obj_get_type_str(o_in)));
     }
 }
 
diff --git a/py/obj.h b/py/obj.h
index dd80b3f021..1daa943447 100644
--- a/py/obj.h
+++ b/py/obj.h
@@ -330,6 +330,7 @@ mp_obj_t mp_obj_complex_binary_op(int op, mp_float_t lhs_real, mp_float_t lhs_im
 extern const mp_obj_type_t tuple_type;
 void mp_obj_tuple_get(mp_obj_t self_in, uint *len, mp_obj_t **items);
 void mp_obj_tuple_del(mp_obj_t self_in);
+machine_int_t mp_obj_tuple_hash(mp_obj_t self_in);
 
 // list
 extern const mp_obj_type_t list_type;
diff --git a/py/objtuple.c b/py/objtuple.c
index 83d1f21cea..3378b4ec1c 100644
--- a/py/objtuple.c
+++ b/py/objtuple.c
@@ -218,6 +218,17 @@ void mp_obj_tuple_del(mp_obj_t self_in) {
     m_del_var(mp_obj_tuple_t, mp_obj_t, self->len, self);
 }
 
+machine_int_t mp_obj_tuple_hash(mp_obj_t self_in) {
+    assert(MP_OBJ_IS_TYPE(self_in, &tuple_type));
+    mp_obj_tuple_t *self = self_in;
+    // start hash with pointer to empty tuple, to make it fairly unique
+    machine_int_t hash = (machine_int_t)mp_const_empty_tuple;
+    for (uint i = 0; i < self->len; i++) {
+        hash += mp_obj_hash(self->items[i]);
+    }
+    return hash;
+}
+
 /******************************************************************************/
 /* tuple iterator                                                             */