Handle map iterator reset for reuse + fix example

[Faker-09]

Reset the handle_map iterators for easy reuse and make the example more compilable.

[Kelimion]

I propose a slightly different diff to make the example more easily compileable:

1. Demonstrate is_valid to use h3 and h in the iterator loop.
2. Add #optional_allocator_error to the dynamic map to mirror the static version's #optional_ok, so neither needs , _ to get rid of ok or err respectively.

Also, your , ok1 doesn't actually use that ok1 anywhere I can see in the diff. Neither are the new err0 and err1, so it wouldn't compile with -vet.

This does. But please do keep the it.index = 0 to make iterating again easier. :-)

diff --git a/core/container/handle_map/doc.odin b/core/container/handle_map/doc.odin
index fe4154774..088ba37d7 100644
--- a/core/container/handle_map/doc.odin
+++ b/core/container/handle_map/doc.odin
@@ -24,10 +24,12 @@ Example:
                hm.remove(&entities, h1)

                h3 := hm.add(&entities, Entity{pos = {6, 7}})
+               assert(hm.is_valid(entities, h3))

                it := hm.iterator_make(&entities)
                for e, h in hm.iterate(&it) {
                        e.pos += {1, 2}
+                       assert(hm.is_valid(entities, h))
                }
        }

@@ -46,10 +48,12 @@ Example:
                hm.remove(&entities, h1)

                h3 := hm.add(&entities, Entity{pos = {6, 7}})
+               assert(hm.is_valid(&entities, h3))

                it := hm.iterator_make(&entities)
                for e, h in hm.iterate(&it) {
                        e.pos += {1, 2}
+                       assert(hm.is_valid(&entities, h))
                }
        }
 */
diff --git a/core/container/handle_map/dynamic_handle_map.odin b/core/container/handle_map/dynamic_handle_map.odin
index 4024ac5b6..bdd9b7daf 100644
--- a/core/container/handle_map/dynamic_handle_map.odin
+++ b/core/container/handle_map/dynamic_handle_map.odin
@@ -31,7 +31,7 @@ dynamic_destroy :: proc(m: ^$D/Dynamic_Handle_Map($T, $Handle_Type)) {
 }

 @(require_results)
-dynamic_add :: proc(m: ^$D/Dynamic_Handle_Map($T, $Handle_Type), item: T, loc := #caller_location) -> (handle: Handle_Type, err: runtime.Allocator_Error) {
+dynamic_add :: proc(m: ^$D/Dynamic_Handle_Map($T, $Handle_Type), item: T, loc := #caller_location) -> (handle: Handle_Type, err: runtime.Allocator_Error) #optional_allocator_error {
        if xar.len(m.unused_items) > 0 {
                i := xar.pop(&m.unused_items)
                ptr := xar.get_ptr_unsafe(&m.items, i)

[Faker-09]

I've made those updates. One minor change to move the assert above the access to e.pos. Thanks!

[Kelimion]

Squahed and merged. Thanks. :-)