1 files changed, 60 insertions, 0 deletions
diff --git a/py/objmap.c b/py/objmap.c
new file mode 100644
index 0000000000..365735283a
--- /dev/null
+++ b/py/objmap.c
@@ -0,0 +1,60 @@
+#include <stdlib.h>
+#include <assert.h>
+
+#include "nlr.h"
+#include "misc.h"
+#include "mpconfig.h"
+#include "mpqstr.h"
+#include "obj.h"
+#include "runtime.h"
+
+typedef struct _mp_obj_map_t {
+    mp_obj_base_t base;
+    machine_uint_t n_iters;
+    mp_obj_t fun;
+    mp_obj_t iters[];
+} mp_obj_map_t;
+
+static mp_obj_t map_make_new(mp_obj_t type_in, int n_args, const mp_obj_t *args) {
+    /* NOTE: args are backwards */
+    if (n_args < 2) {
+        nlr_jump(mp_obj_new_exception_msg(MP_QSTR_TypeError, "map must have at least 2 arguments"));
+    }
+    assert(n_args >= 2);
+    mp_obj_map_t *o = m_new_obj_var(mp_obj_map_t, mp_obj_t, n_args - 1);
+    o->base.type = &map_type;
+    o->n_iters = n_args - 1;
+    o->fun = args[n_args - 1];
+    for (int i = 0; i < n_args - 1; i++) {
+        o->iters[i] = rt_getiter(args[n_args-i-2]);
+    }
+    return o;
+}
+
+static mp_obj_t map_getiter(mp_obj_t self_in) {
+    return self_in;
+}
+
+static mp_obj_t map_iternext(mp_obj_t self_in) {
+    assert(MP_OBJ_IS_TYPE(self_in, &map_type));
+    mp_obj_map_t *self = self_in;
+    mp_obj_t *nextses = m_new(mp_obj_t, self->n_iters);
+
+    for (int i = 0; i < self->n_iters; i++) {
+        mp_obj_t next = rt_iternext(self->iters[i]);
+        if (next == mp_const_stop_iteration) {
+            m_del(mp_obj_t, nextses, self->n_iters);
+            return mp_const_stop_iteration;
+        }
+        nextses[i] = next;
+    }
+    return rt_call_function_n(self->fun, self->n_iters, nextses);
+}
+
+const mp_obj_type_t map_type = {
+    { &mp_const_type },
+    "map",
+    .make_new = map_make_new,
+    .getiter = map_getiter,
+    .iternext = map_iternext,
+};