diff --git a/extmod/modbtree.c b/extmod/modbtree.c
index 229daaf0f9..5017079da3 100644
--- a/extmod/modbtree.c
+++ b/extmod/modbtree.c
@@ -281,7 +281,7 @@ STATIC mp_obj_t btree_subscr(mp_obj_t self_in, mp_obj_t index, mp_obj_t value) {
     }
 }
 
-STATIC mp_obj_t btree_binary_op(mp_uint_t op, mp_obj_t lhs_in, mp_obj_t rhs_in) {
+STATIC mp_obj_t btree_binary_op(mp_binary_op_t op, mp_obj_t lhs_in, mp_obj_t rhs_in) {
     mp_obj_btree_t *self = MP_OBJ_TO_PTR(lhs_in);
     switch (op) {
         case MP_BINARY_OP_IN: {
diff --git a/extmod/modutimeq.c b/extmod/modutimeq.c
index a19b3fda9a..faa5895830 100644
--- a/extmod/modutimeq.c
+++ b/extmod/modutimeq.c
@@ -189,7 +189,7 @@ STATIC mp_obj_t mod_utimeq_dump(mp_obj_t heap_in) {
 STATIC MP_DEFINE_CONST_FUN_OBJ_1(mod_utimeq_dump_obj, mod_utimeq_dump);
 #endif
 
-STATIC mp_obj_t utimeq_unary_op(mp_uint_t op, mp_obj_t self_in) {
+STATIC mp_obj_t utimeq_unary_op(mp_unary_op_t op, mp_obj_t self_in) {
     mp_obj_utimeq_t *self = MP_OBJ_TO_PTR(self_in);
     switch (op) {
         case MP_UNARY_OP_BOOL: return mp_obj_new_bool(self->len != 0);
diff --git a/py/obj.c b/py/obj.c
index 515a95b2e4..0dab5f2ac7 100644
--- a/py/obj.c
+++ b/py/obj.c
@@ -505,7 +505,7 @@ void mp_get_buffer_raise(mp_obj_t obj, mp_buffer_info_t *bufinfo, mp_uint_t flag
     }
 }
 
-mp_obj_t mp_generic_unary_op(mp_uint_t op, mp_obj_t o_in) {
+mp_obj_t mp_generic_unary_op(mp_unary_op_t op, mp_obj_t o_in) {
     switch (op) {
         case MP_UNARY_OP_HASH: return MP_OBJ_NEW_SMALL_INT((mp_uint_t)o_in);
         default: return MP_OBJ_NULL; // op not supported
diff --git a/py/obj.h b/py/obj.h
index 22bfda0f99..2adcab1a6e 100644
--- a/py/obj.h
+++ b/py/obj.h
@@ -30,6 +30,7 @@
 #include "py/misc.h"
 #include "py/qstr.h"
 #include "py/mpprint.h"
+#include "py/runtime0.h"
 
 // This is the definition of the opaque MicroPython object type.
 // All concrete objects have an encoding within this type and the
@@ -429,8 +430,8 @@ typedef struct _mp_obj_iter_buf_t {
 typedef void (*mp_print_fun_t)(const mp_print_t *print, mp_obj_t o, mp_print_kind_t kind);
 typedef mp_obj_t (*mp_make_new_fun_t)(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *args);
 typedef mp_obj_t (*mp_call_fun_t)(mp_obj_t fun, size_t n_args, size_t n_kw, const mp_obj_t *args);
-typedef mp_obj_t (*mp_unary_op_fun_t)(mp_uint_t op, mp_obj_t);
-typedef mp_obj_t (*mp_binary_op_fun_t)(mp_uint_t op, mp_obj_t, mp_obj_t);
+typedef mp_obj_t (*mp_unary_op_fun_t)(mp_unary_op_t op, mp_obj_t);
+typedef mp_obj_t (*mp_binary_op_fun_t)(mp_binary_op_t op, mp_obj_t, mp_obj_t);
 typedef void (*mp_attr_fun_t)(mp_obj_t self_in, qstr attr, mp_obj_t *dest);
 typedef mp_obj_t (*mp_subscr_fun_t)(mp_obj_t self_in, mp_obj_t index, mp_obj_t value);
 typedef mp_obj_t (*mp_getiter_fun_t)(mp_obj_t self_in, mp_obj_iter_buf_t *iter_buf);
@@ -694,7 +695,7 @@ mp_obj_t mp_obj_id(mp_obj_t o_in);
 mp_obj_t mp_obj_len(mp_obj_t o_in);
 mp_obj_t mp_obj_len_maybe(mp_obj_t o_in); // may return MP_OBJ_NULL
 mp_obj_t mp_obj_subscr(mp_obj_t base, mp_obj_t index, mp_obj_t val);
-mp_obj_t mp_generic_unary_op(mp_uint_t op, mp_obj_t o_in);
+mp_obj_t mp_generic_unary_op(mp_unary_op_t op, mp_obj_t o_in);
 
 // cell
 mp_obj_t mp_obj_cell_get(mp_obj_t self_in);
@@ -734,11 +735,11 @@ mp_int_t mp_float_hash(mp_float_t val);
 #else
 static inline mp_int_t mp_float_hash(mp_float_t val) { return (mp_int_t)val; }
 #endif
-mp_obj_t mp_obj_float_binary_op(mp_uint_t op, mp_float_t lhs_val, mp_obj_t rhs); // can return MP_OBJ_NULL if op not supported
+mp_obj_t mp_obj_float_binary_op(mp_binary_op_t op, mp_float_t lhs_val, mp_obj_t rhs); // can return MP_OBJ_NULL if op not supported
 
 // complex
 void mp_obj_complex_get(mp_obj_t self_in, mp_float_t *real, mp_float_t *imag);
-mp_obj_t mp_obj_complex_binary_op(mp_uint_t op, mp_float_t lhs_real, mp_float_t lhs_imag, mp_obj_t rhs_in); // can return MP_OBJ_NULL if op not supported
+mp_obj_t mp_obj_complex_binary_op(mp_binary_op_t op, mp_float_t lhs_real, mp_float_t lhs_imag, mp_obj_t rhs_in); // can return MP_OBJ_NULL if op not supported
 #else
 #define mp_obj_is_float(o) (false)
 #endif
diff --git a/py/objarray.c b/py/objarray.c
index a31c536804..d51cc650b0 100644
--- a/py/objarray.c
+++ b/py/objarray.c
@@ -231,7 +231,7 @@ STATIC mp_obj_t memoryview_make_new(const mp_obj_type_t *type_in, size_t n_args,
 }
 #endif
 
-STATIC mp_obj_t array_unary_op(mp_uint_t op, mp_obj_t o_in) {
+STATIC mp_obj_t array_unary_op(mp_unary_op_t op, mp_obj_t o_in) {
     mp_obj_array_t *o = MP_OBJ_TO_PTR(o_in);
     switch (op) {
         case MP_UNARY_OP_BOOL: return mp_obj_new_bool(o->len != 0);
@@ -240,7 +240,7 @@ STATIC mp_obj_t array_unary_op(mp_uint_t op, mp_obj_t o_in) {
     }
 }
 
-STATIC mp_obj_t array_binary_op(mp_uint_t op, mp_obj_t lhs_in, mp_obj_t rhs_in) {
+STATIC mp_obj_t array_binary_op(mp_binary_op_t op, mp_obj_t lhs_in, mp_obj_t rhs_in) {
     mp_obj_array_t *lhs = MP_OBJ_TO_PTR(lhs_in);
     switch (op) {
         case MP_BINARY_OP_ADD: {
diff --git a/py/objbool.c b/py/objbool.c
index e5bc3c2287..b94c57f871 100644
--- a/py/objbool.c
+++ b/py/objbool.c
@@ -63,7 +63,7 @@ STATIC mp_obj_t bool_make_new(const mp_obj_type_t *type_in, size_t n_args, size_
     }
 }
 
-STATIC mp_obj_t bool_unary_op(mp_uint_t op, mp_obj_t o_in) {
+STATIC mp_obj_t bool_unary_op(mp_unary_op_t op, mp_obj_t o_in) {
     if (op == MP_UNARY_OP_LEN) {
         return MP_OBJ_NULL;
     }
@@ -71,7 +71,7 @@ STATIC mp_obj_t bool_unary_op(mp_uint_t op, mp_obj_t o_in) {
     return mp_unary_op(op, MP_OBJ_NEW_SMALL_INT(self->value));
 }
 
-STATIC mp_obj_t bool_binary_op(mp_uint_t op, mp_obj_t lhs_in, mp_obj_t rhs_in) {
+STATIC mp_obj_t bool_binary_op(mp_binary_op_t op, mp_obj_t lhs_in, mp_obj_t rhs_in) {
     mp_obj_bool_t *self = MP_OBJ_TO_PTR(lhs_in);
     return mp_binary_op(op, MP_OBJ_NEW_SMALL_INT(self->value), rhs_in);
 }
diff --git a/py/objcomplex.c b/py/objcomplex.c
index 55627afea2..07b9d5d410 100644
--- a/py/objcomplex.c
+++ b/py/objcomplex.c
@@ -117,7 +117,7 @@ STATIC mp_obj_t complex_make_new(const mp_obj_type_t *type_in, size_t n_args, si
     }
 }
 
-STATIC mp_obj_t complex_unary_op(mp_uint_t op, mp_obj_t o_in) {
+STATIC mp_obj_t complex_unary_op(mp_unary_op_t op, mp_obj_t o_in) {
     mp_obj_complex_t *o = MP_OBJ_TO_PTR(o_in);
     switch (op) {
         case MP_UNARY_OP_BOOL: return mp_obj_new_bool(o->real != 0 || o->imag != 0);
@@ -128,7 +128,7 @@ STATIC mp_obj_t complex_unary_op(mp_uint_t op, mp_obj_t o_in) {
     }
 }
 
-STATIC mp_obj_t complex_binary_op(mp_uint_t op, mp_obj_t lhs_in, mp_obj_t rhs_in) {
+STATIC mp_obj_t complex_binary_op(mp_binary_op_t op, mp_obj_t lhs_in, mp_obj_t rhs_in) {
     mp_obj_complex_t *lhs = MP_OBJ_TO_PTR(lhs_in);
     return mp_obj_complex_binary_op(op, lhs->real, lhs->imag, rhs_in);
 }
@@ -171,7 +171,7 @@ void mp_obj_complex_get(mp_obj_t self_in, mp_float_t *real, mp_float_t *imag) {
     *imag = self->imag;
 }
 
-mp_obj_t mp_obj_complex_binary_op(mp_uint_t op, mp_float_t lhs_real, mp_float_t lhs_imag, mp_obj_t rhs_in) {
+mp_obj_t mp_obj_complex_binary_op(mp_binary_op_t op, mp_float_t lhs_real, mp_float_t lhs_imag, mp_obj_t rhs_in) {
     mp_float_t rhs_real, rhs_imag;
     mp_obj_get_complex(rhs_in, &rhs_real, &rhs_imag); // can be any type, this function will convert to float (if possible)
     switch (op) {
diff --git a/py/objdict.c b/py/objdict.c
index f6357a905b..6bb2435626 100644
--- a/py/objdict.c
+++ b/py/objdict.c
@@ -100,7 +100,7 @@ STATIC mp_obj_t dict_make_new(const mp_obj_type_t *type, size_t n_args, size_t n
     return dict_out;
 }
 
-STATIC mp_obj_t dict_unary_op(mp_uint_t op, mp_obj_t self_in) {
+STATIC mp_obj_t dict_unary_op(mp_unary_op_t op, mp_obj_t self_in) {
     mp_obj_dict_t *self = MP_OBJ_TO_PTR(self_in);
     switch (op) {
         case MP_UNARY_OP_BOOL: return mp_obj_new_bool(self->map.used != 0);
@@ -115,7 +115,7 @@ STATIC mp_obj_t dict_unary_op(mp_uint_t op, mp_obj_t self_in) {
     }
 }
 
-STATIC mp_obj_t dict_binary_op(mp_uint_t op, mp_obj_t lhs_in, mp_obj_t rhs_in) {
+STATIC mp_obj_t dict_binary_op(mp_binary_op_t op, mp_obj_t lhs_in, mp_obj_t rhs_in) {
     mp_obj_dict_t *o = MP_OBJ_TO_PTR(lhs_in);
     switch (op) {
         case MP_BINARY_OP_IN: {
@@ -482,7 +482,7 @@ STATIC void dict_view_print(const mp_print_t *print, mp_obj_t self_in, mp_print_
     mp_print_str(print, "])");
 }
 
-STATIC mp_obj_t dict_view_binary_op(mp_uint_t op, mp_obj_t lhs_in, mp_obj_t rhs_in) {
+STATIC mp_obj_t dict_view_binary_op(mp_binary_op_t op, mp_obj_t lhs_in, mp_obj_t rhs_in) {
     // only supported for the 'keys' kind until sets and dicts are refactored
     mp_obj_dict_view_t *o = MP_OBJ_TO_PTR(lhs_in);
     if (o->kind != MP_DICT_VIEW_KEYS) {
diff --git a/py/objfloat.c b/py/objfloat.c
index 15edd810f1..b1900b236c 100644
--- a/py/objfloat.c
+++ b/py/objfloat.c
@@ -155,7 +155,7 @@ STATIC mp_obj_t float_make_new(const mp_obj_type_t *type_in, size_t n_args, size
     }
 }
 
-STATIC mp_obj_t float_unary_op(mp_uint_t op, mp_obj_t o_in) {
+STATIC mp_obj_t float_unary_op(mp_unary_op_t op, mp_obj_t o_in) {
     mp_float_t val = mp_obj_float_get(o_in);
     switch (op) {
         case MP_UNARY_OP_BOOL: return mp_obj_new_bool(val != 0);
@@ -166,7 +166,7 @@ STATIC mp_obj_t float_unary_op(mp_uint_t op, mp_obj_t o_in) {
     }
 }
 
-STATIC mp_obj_t float_binary_op(mp_uint_t op, mp_obj_t lhs_in, mp_obj_t rhs_in) {
+STATIC mp_obj_t float_binary_op(mp_binary_op_t op, mp_obj_t lhs_in, mp_obj_t rhs_in) {
     mp_float_t lhs_val = mp_obj_float_get(lhs_in);
 #if MICROPY_PY_BUILTINS_COMPLEX
     if (MP_OBJ_IS_TYPE(rhs_in, &mp_type_complex)) {
@@ -239,7 +239,7 @@ STATIC void mp_obj_float_divmod(mp_float_t *x, mp_float_t *y) {
     *y = mod;
 }
 
-mp_obj_t mp_obj_float_binary_op(mp_uint_t op, mp_float_t lhs_val, mp_obj_t rhs_in) {
+mp_obj_t mp_obj_float_binary_op(mp_binary_op_t op, mp_float_t lhs_val, mp_obj_t rhs_in) {
     mp_float_t rhs_val = mp_obj_get_float(rhs_in); // can be any type, this function will convert to float (if possible)
     switch (op) {
         case MP_BINARY_OP_ADD:
diff --git a/py/objint.c b/py/objint.c
index 29d889629f..6a73b43825 100644
--- a/py/objint.c
+++ b/py/objint.c
@@ -325,12 +325,12 @@ mp_obj_t mp_obj_int_abs(mp_obj_t self_in) {
 }
 
 // This is called for operations on SMALL_INT that are not handled by mp_unary_op
-mp_obj_t mp_obj_int_unary_op(mp_uint_t op, mp_obj_t o_in) {
+mp_obj_t mp_obj_int_unary_op(mp_unary_op_t op, mp_obj_t o_in) {
     return MP_OBJ_NULL; // op not supported
 }
 
 // This is called for operations on SMALL_INT that are not handled by mp_binary_op
-mp_obj_t mp_obj_int_binary_op(mp_uint_t op, mp_obj_t lhs_in, mp_obj_t rhs_in) {
+mp_obj_t mp_obj_int_binary_op(mp_binary_op_t op, mp_obj_t lhs_in, mp_obj_t rhs_in) {
     return mp_obj_int_binary_op_extra_cases(op, lhs_in, rhs_in);
 }
 
@@ -382,7 +382,7 @@ mp_int_t mp_obj_int_get_checked(mp_const_obj_t self_in) {
 
 // This dispatcher function is expected to be independent of the implementation of long int
 // It handles the extra cases for integer-like arithmetic
-mp_obj_t mp_obj_int_binary_op_extra_cases(mp_uint_t op, mp_obj_t lhs_in, mp_obj_t rhs_in) {
+mp_obj_t mp_obj_int_binary_op_extra_cases(mp_binary_op_t op, mp_obj_t lhs_in, mp_obj_t rhs_in) {
     if (rhs_in == mp_const_false) {
         // false acts as 0
         return mp_binary_op(op, lhs_in, MP_OBJ_NEW_SMALL_INT(0));
diff --git a/py/objint.h b/py/objint.h
index 394c23714b..a4d4ff32d8 100644
--- a/py/objint.h
+++ b/py/objint.h
@@ -58,9 +58,9 @@ mp_obj_t mp_obj_int_from_bytes_impl(bool big_endian, size_t len, const byte *buf
 void mp_obj_int_to_bytes_impl(mp_obj_t self_in, bool big_endian, size_t len, byte *buf);
 int mp_obj_int_sign(mp_obj_t self_in);
 mp_obj_t mp_obj_int_abs(mp_obj_t self_in);
-mp_obj_t mp_obj_int_unary_op(mp_uint_t op, mp_obj_t o_in);
-mp_obj_t mp_obj_int_binary_op(mp_uint_t op, mp_obj_t lhs_in, mp_obj_t rhs_in);
-mp_obj_t mp_obj_int_binary_op_extra_cases(mp_uint_t op, mp_obj_t lhs_in, mp_obj_t rhs_in);
+mp_obj_t mp_obj_int_unary_op(mp_unary_op_t op, mp_obj_t o_in);
+mp_obj_t mp_obj_int_binary_op(mp_binary_op_t op, mp_obj_t lhs_in, mp_obj_t rhs_in);
+mp_obj_t mp_obj_int_binary_op_extra_cases(mp_binary_op_t op, mp_obj_t lhs_in, mp_obj_t rhs_in);
 mp_obj_t mp_obj_int_pow3(mp_obj_t base, mp_obj_t exponent,  mp_obj_t modulus);
 
 #endif // MICROPY_INCLUDED_PY_OBJINT_H
diff --git a/py/objint_longlong.c b/py/objint_longlong.c
index 02c005d2fd..ddfdae744e 100644
--- a/py/objint_longlong.c
+++ b/py/objint_longlong.c
@@ -118,7 +118,7 @@ mp_obj_t mp_obj_int_abs(mp_obj_t self_in) {
     }
 }
 
-mp_obj_t mp_obj_int_unary_op(mp_uint_t op, mp_obj_t o_in) {
+mp_obj_t mp_obj_int_unary_op(mp_unary_op_t op, mp_obj_t o_in) {
     mp_obj_int_t *o = o_in;
     switch (op) {
         case MP_UNARY_OP_BOOL: return mp_obj_new_bool(o->val != 0);
@@ -134,7 +134,7 @@ mp_obj_t mp_obj_int_unary_op(mp_uint_t op, mp_obj_t o_in) {
     }
 }
 
-mp_obj_t mp_obj_int_binary_op(mp_uint_t op, mp_obj_t lhs_in, mp_obj_t rhs_in) {
+mp_obj_t mp_obj_int_binary_op(mp_binary_op_t op, mp_obj_t lhs_in, mp_obj_t rhs_in) {
     long long lhs_val;
     long long rhs_val;
 
diff --git a/py/objint_mpz.c b/py/objint_mpz.c
index 0791a8af2c..148446f0fc 100644
--- a/py/objint_mpz.c
+++ b/py/objint_mpz.c
@@ -162,7 +162,7 @@ mp_obj_t mp_obj_int_abs(mp_obj_t self_in) {
     }
 }
 
-mp_obj_t mp_obj_int_unary_op(mp_uint_t op, mp_obj_t o_in) {
+mp_obj_t mp_obj_int_unary_op(mp_unary_op_t op, mp_obj_t o_in) {
     mp_obj_int_t *o = MP_OBJ_TO_PTR(o_in);
     switch (op) {
         case MP_UNARY_OP_BOOL: return mp_obj_new_bool(!mpz_is_zero(&o->mpz));
@@ -174,7 +174,7 @@ mp_obj_t mp_obj_int_unary_op(mp_uint_t op, mp_obj_t o_in) {
     }
 }
 
-mp_obj_t mp_obj_int_binary_op(mp_uint_t op, mp_obj_t lhs_in, mp_obj_t rhs_in) {
+mp_obj_t mp_obj_int_binary_op(mp_binary_op_t op, mp_obj_t lhs_in, mp_obj_t rhs_in) {
     const mpz_t *zlhs;
     const mpz_t *zrhs;
     mpz_t z_int;
diff --git a/py/objlist.c b/py/objlist.c
index 86d4300620..6ac33e80e6 100644
--- a/py/objlist.c
+++ b/py/objlist.c
@@ -99,7 +99,7 @@ STATIC bool list_cmp_helper(mp_uint_t op, mp_obj_t self_in, mp_obj_t another_in)
     return mp_seq_cmp_objs(op, self->items, self->len, another->items, another->len);
 }
 
-STATIC mp_obj_t list_unary_op(mp_uint_t op, mp_obj_t self_in) {
+STATIC mp_obj_t list_unary_op(mp_unary_op_t op, mp_obj_t self_in) {
     mp_obj_list_t *self = MP_OBJ_TO_PTR(self_in);
     switch (op) {
         case MP_UNARY_OP_BOOL: return mp_obj_new_bool(self->len != 0);
@@ -114,7 +114,7 @@ STATIC mp_obj_t list_unary_op(mp_uint_t op, mp_obj_t self_in) {
     }
 }
 
-STATIC mp_obj_t list_binary_op(mp_uint_t op, mp_obj_t lhs, mp_obj_t rhs) {
+STATIC mp_obj_t list_binary_op(mp_binary_op_t op, mp_obj_t lhs, mp_obj_t rhs) {
     mp_obj_list_t *o = MP_OBJ_TO_PTR(lhs);
     switch (op) {
         case MP_BINARY_OP_ADD: {
diff --git a/py/objrange.c b/py/objrange.c
index 33b07a9d44..fa99c4c2db 100644
--- a/py/objrange.c
+++ b/py/objrange.c
@@ -130,7 +130,7 @@ STATIC mp_int_t range_len(mp_obj_range_t *self) {
     return len;
 }
 
-STATIC mp_obj_t range_unary_op(mp_uint_t op, mp_obj_t self_in) {
+STATIC mp_obj_t range_unary_op(mp_unary_op_t op, mp_obj_t self_in) {
     mp_obj_range_t *self = MP_OBJ_TO_PTR(self_in);
     mp_int_t len = range_len(self);
     switch (op) {
diff --git a/py/objset.c b/py/objset.c
index 376439b73e..d4a8a1a39b 100644
--- a/py/objset.c
+++ b/py/objset.c
@@ -455,7 +455,7 @@ STATIC mp_obj_t set_union(mp_obj_t self_in, mp_obj_t other_in) {
 }
 STATIC MP_DEFINE_CONST_FUN_OBJ_2(set_union_obj, set_union);
 
-STATIC mp_obj_t set_unary_op(mp_uint_t op, mp_obj_t self_in) {
+STATIC mp_obj_t set_unary_op(mp_unary_op_t op, mp_obj_t self_in) {
     mp_obj_set_t *self = MP_OBJ_TO_PTR(self_in);
     switch (op) {
         case MP_UNARY_OP_BOOL: return mp_obj_new_bool(self->set.used != 0);
@@ -480,7 +480,7 @@ STATIC mp_obj_t set_unary_op(mp_uint_t op, mp_obj_t self_in) {
     }
 }
 
-STATIC mp_obj_t set_binary_op(mp_uint_t op, mp_obj_t lhs, mp_obj_t rhs) {
+STATIC mp_obj_t set_binary_op(mp_binary_op_t op, mp_obj_t lhs, mp_obj_t rhs) {
     mp_obj_t args[] = {lhs, rhs};
     #if MICROPY_PY_BUILTINS_FROZENSET
     bool update = MP_OBJ_IS_TYPE(lhs, &mp_type_set);
diff --git a/py/objstr.c b/py/objstr.c
index f04bd90be7..4c287af040 100644
--- a/py/objstr.c
+++ b/py/objstr.c
@@ -280,7 +280,7 @@ const byte *find_subbytes(const byte *haystack, size_t hlen, const byte *needle,
 // Note: this function is used to check if an object is a str or bytes, which
 // works because both those types use it as their binary_op method.  Revisit
 // MP_OBJ_IS_STR_OR_BYTES if this fact changes.
-mp_obj_t mp_obj_str_binary_op(mp_uint_t op, mp_obj_t lhs_in, mp_obj_t rhs_in) {
+mp_obj_t mp_obj_str_binary_op(mp_binary_op_t op, mp_obj_t lhs_in, mp_obj_t rhs_in) {
     // check for modulo
     if (op == MP_BINARY_OP_MODULO) {
         mp_obj_t *args = &rhs_in;
@@ -380,9 +380,10 @@ mp_obj_t mp_obj_str_binary_op(mp_uint_t op, mp_obj_t lhs_in, mp_obj_t rhs_in) {
         case MP_BINARY_OP_MORE:
         case MP_BINARY_OP_MORE_EQUAL:
             return mp_obj_new_bool(mp_seq_cmp_bytes(op, lhs_data, lhs_len, rhs_data, rhs_len));
-    }
 
-    return MP_OBJ_NULL; // op not supported
+        default:
+            return MP_OBJ_NULL; // op not supported
+    }
 }
 
 #if !MICROPY_PY_BUILTINS_STR_UNICODE
diff --git a/py/objstr.h b/py/objstr.h
index 3aef8c68e2..82501a763e 100644
--- a/py/objstr.h
+++ b/py/objstr.h
@@ -67,7 +67,7 @@ mp_obj_t mp_obj_str_format(size_t n_args, const mp_obj_t *args, mp_map_t *kwargs
 mp_obj_t mp_obj_str_split(size_t n_args, const mp_obj_t *args);
 mp_obj_t mp_obj_new_str_of_type(const mp_obj_type_t *type, const byte* data, size_t len);
 
-mp_obj_t mp_obj_str_binary_op(mp_uint_t op, mp_obj_t lhs_in, mp_obj_t rhs_in);
+mp_obj_t mp_obj_str_binary_op(mp_binary_op_t op, mp_obj_t lhs_in, mp_obj_t rhs_in);
 mp_int_t mp_obj_str_get_buffer(mp_obj_t self_in, mp_buffer_info_t *bufinfo, mp_uint_t flags);
 
 const byte *str_index_to_ptr(const mp_obj_type_t *type, const byte *self_data, size_t self_len,
diff --git a/py/objstrunicode.c b/py/objstrunicode.c
index 036f7f3c14..785317406b 100644
--- a/py/objstrunicode.c
+++ b/py/objstrunicode.c
@@ -100,7 +100,7 @@ STATIC void uni_print(const mp_print_t *print, mp_obj_t self_in, mp_print_kind_t
     }
 }
 
-STATIC mp_obj_t uni_unary_op(mp_uint_t op, mp_obj_t self_in) {
+STATIC mp_obj_t uni_unary_op(mp_unary_op_t op, mp_obj_t self_in) {
     GET_STR_DATA_LEN(self_in, str_data, str_len);
     switch (op) {
         case MP_UNARY_OP_BOOL:
diff --git a/py/objtuple.c b/py/objtuple.c
index 765edb907c..079b5cbdb7 100644
--- a/py/objtuple.c
+++ b/py/objtuple.c
@@ -118,7 +118,7 @@ STATIC bool tuple_cmp_helper(mp_uint_t op, mp_obj_t self_in, mp_obj_t another_in
     return mp_seq_cmp_objs(op, self->items, self->len, another->items, another->len);
 }
 
-mp_obj_t mp_obj_tuple_unary_op(mp_uint_t op, mp_obj_t self_in) {
+mp_obj_t mp_obj_tuple_unary_op(mp_unary_op_t op, mp_obj_t self_in) {
     mp_obj_tuple_t *self = MP_OBJ_TO_PTR(self_in);
     switch (op) {
         case MP_UNARY_OP_BOOL: return mp_obj_new_bool(self->len != 0);
@@ -135,7 +135,7 @@ mp_obj_t mp_obj_tuple_unary_op(mp_uint_t op, mp_obj_t self_in) {
     }
 }
 
-mp_obj_t mp_obj_tuple_binary_op(mp_uint_t op, mp_obj_t lhs, mp_obj_t rhs) {
+mp_obj_t mp_obj_tuple_binary_op(mp_binary_op_t op, mp_obj_t lhs, mp_obj_t rhs) {
     mp_obj_tuple_t *o = MP_OBJ_TO_PTR(lhs);
     switch (op) {
         case MP_BINARY_OP_ADD:
diff --git a/py/objtuple.h b/py/objtuple.h
index 05c6490fe6..74cde88d3d 100644
--- a/py/objtuple.h
+++ b/py/objtuple.h
@@ -41,8 +41,8 @@ typedef struct _mp_rom_obj_tuple_t {
 } mp_rom_obj_tuple_t;
 
 void mp_obj_tuple_print(const mp_print_t *print, mp_obj_t o_in, mp_print_kind_t kind);
-mp_obj_t mp_obj_tuple_unary_op(mp_uint_t op, mp_obj_t self_in);
-mp_obj_t mp_obj_tuple_binary_op(mp_uint_t op, mp_obj_t lhs, mp_obj_t rhs);
+mp_obj_t mp_obj_tuple_unary_op(mp_unary_op_t op, mp_obj_t self_in);
+mp_obj_t mp_obj_tuple_binary_op(mp_binary_op_t op, mp_obj_t lhs, mp_obj_t rhs);
 mp_obj_t mp_obj_tuple_subscr(mp_obj_t base, mp_obj_t index, mp_obj_t value);
 mp_obj_t mp_obj_tuple_getiter(mp_obj_t o_in, mp_obj_iter_buf_t *iter_buf);
 
diff --git a/py/objtype.c b/py/objtype.c
index e1a24da7e7..08e276d72e 100644
--- a/py/objtype.c
+++ b/py/objtype.c
@@ -345,7 +345,7 @@ const qstr mp_unary_op_method_name[] = {
     [MP_UNARY_OP_NOT] = MP_QSTR_, // don't need to implement this, used to make sure array has full size
 };
 
-STATIC mp_obj_t instance_unary_op(mp_uint_t op, mp_obj_t self_in) {
+STATIC mp_obj_t instance_unary_op(mp_unary_op_t op, mp_obj_t self_in) {
     mp_obj_instance_t *self = MP_OBJ_TO_PTR(self_in);
 
     #if MICROPY_PY_SYS_GETSIZEOF
@@ -452,7 +452,7 @@ const qstr mp_binary_op_method_name[] = {
     [MP_BINARY_OP_EXCEPTION_MATCH] = MP_QSTR_, // not implemented, used to make sure array has full size
 };
 
-STATIC mp_obj_t instance_binary_op(mp_uint_t op, mp_obj_t lhs_in, mp_obj_t rhs_in) {
+STATIC mp_obj_t instance_binary_op(mp_binary_op_t op, mp_obj_t lhs_in, mp_obj_t rhs_in) {
     // Note: For ducktyping, CPython does not look in the instance members or use
     // __getattr__ or __getattribute__.  It only looks in the class dictionary.
     mp_obj_instance_t *lhs = MP_OBJ_TO_PTR(lhs_in);
diff --git a/py/runtime.c b/py/runtime.c
index eb1298813f..1db6c93c30 100644
--- a/py/runtime.c
+++ b/py/runtime.c
@@ -209,7 +209,7 @@ void mp_delete_global(qstr qst) {
     mp_obj_dict_delete(MP_OBJ_FROM_PTR(mp_globals_get()), MP_OBJ_NEW_QSTR(qst));
 }
 
-mp_obj_t mp_unary_op(mp_uint_t op, mp_obj_t arg) {
+mp_obj_t mp_unary_op(mp_unary_op_t op, mp_obj_t arg) {
     DEBUG_OP_printf("unary " UINT_FMT " %p\n", op, arg);
 
     if (op == MP_UNARY_OP_NOT) {
@@ -261,7 +261,7 @@ mp_obj_t mp_unary_op(mp_uint_t op, mp_obj_t arg) {
     }
 }
 
-mp_obj_t mp_binary_op(mp_uint_t op, mp_obj_t lhs, mp_obj_t rhs) {
+mp_obj_t mp_binary_op(mp_binary_op_t op, mp_obj_t lhs, mp_obj_t rhs) {
     DEBUG_OP_printf("binary " UINT_FMT " %p %p\n", op, lhs, rhs);
 
     // TODO correctly distinguish inplace operators for mutable objects
diff --git a/py/runtime.h b/py/runtime.h
index 428e2571cc..4abdea5840 100644
--- a/py/runtime.h
+++ b/py/runtime.h
@@ -96,8 +96,8 @@ void mp_store_global(qstr qst, mp_obj_t obj);
 void mp_delete_name(qstr qst);
 void mp_delete_global(qstr qst);
 
-mp_obj_t mp_unary_op(mp_uint_t op, mp_obj_t arg);
-mp_obj_t mp_binary_op(mp_uint_t op, mp_obj_t lhs, mp_obj_t rhs);
+mp_obj_t mp_unary_op(mp_unary_op_t op, mp_obj_t arg);
+mp_obj_t mp_binary_op(mp_binary_op_t op, mp_obj_t lhs, mp_obj_t rhs);
 
 mp_obj_t mp_call_function_0(mp_obj_t fun);
 mp_obj_t mp_call_function_1(mp_obj_t fun, mp_obj_t arg);
diff --git a/unix/modjni.c b/unix/modjni.c
index df9cd9d67a..85fc891448 100644
--- a/unix/modjni.c
+++ b/unix/modjni.c
@@ -293,7 +293,7 @@ STATIC mp_obj_t jobject_subscr(mp_obj_t self_in, mp_obj_t index, mp_obj_t value)
 return MP_OBJ_NULL;
 }
 
-STATIC mp_obj_t jobject_unary_op(mp_uint_t op, mp_obj_t self_in) {
+STATIC mp_obj_t jobject_unary_op(mp_unary_op_t op, mp_obj_t self_in) {
     mp_obj_jobject_t *self = self_in;
     switch (op) {
         case MP_UNARY_OP_BOOL: