refactor(map): avoid duplicated khash_t types for values

This reduces the total number of khash_t instantiations from 22 to 8.

Make the khash internal functions take the size of values as a runtime
parameter. This is abstracted with typesafe Map containers which
are still specialized for both key, value type.

Introduce `Set(key)` type for when there is no value.

Refactor shada.c to use Map/Set instead of khash directly.
This requires `map_ref` operation to be more flexible.
Return pointers to both key and value, plus an indicator for new_item.
As a bonus, `map_key` is now redundant.

Instead of Map(cstr_t, FileMarks), use a pointer map as the FileMarks struct is
humongous.

Make `event_strings` actually work like an intern pool instead of wtf it
was doing before.

1 files changed, 4 insertions, 6 deletions

diff --git a/src/nvim/api/extmark.c b/src/nvim/api/extmark.c
index 87232a8a93..d6f0288f94 100644
--- a/src/nvim/api/extmark.c
+++ b/src/nvim/api/extmark.c
@@ -33,12 +33,10 @@
 void api_extmark_free_all_mem(void)
 {
   String name;
-  handle_T id;
-  map_foreach(&namespace_ids, name, id, {
-    (void)id;
+  map_foreach_key(&namespace_ids, name, {
     xfree(name.data);
   })
-  map_destroy(String, handle_T)(&namespace_ids);
+  map_destroy(String, &namespace_ids);
 }
 
 /// Creates a new namespace or gets an existing one. \*namespace\*
@@ -77,7 +75,7 @@ Dictionary nvim_get_namespaces(void)
   String name;
   handle_T id;
 
-  map_foreach(&namespace_ids, name, id, {
+  map_foreach(handle_T, &namespace_ids, name, id, {
     PUT(retval, name.data, INTEGER_OBJ(id));
   })
 
@@ -88,7 +86,7 @@ const char *describe_ns(NS ns_id)
 {
   String name;
   handle_T id;
-  map_foreach(&namespace_ids, name, id, {
+  map_foreach(handle_T, &namespace_ids, name, id, {
     if ((NS)id == ns_id && name.size) {
       return name.data;
     }