From 8d2430e54d40bb705499f5cfeef9fead6d9ad833 Mon Sep 17 00:00:00 2001
From: Tetralux <tetralux@teknik.io>
Date: Thu, 7 May 2020 00:32:35 +0000
Subject: [PATCH] Add reflect.enum_from_name

Provides a way to go from a enum value name string to an actual enum value.

```
E :: enum { A, B }

// ...

s := "B";
v, ok := enum_from_name(E, s);
assert(ok && v == E.B);
```
---
 core/reflect/reflect.odin | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/core/reflect/reflect.odin b/core/reflect/reflect.odin
index 12428d59c..f92dc1f39 100644
--- a/core/reflect/reflect.odin
+++ b/core/reflect/reflect.odin
@@ -510,6 +510,34 @@ enum_string :: proc(a: any) -> string {
 	return "";
 }
 
+// Given a enum type and a value name, get the enum value.
+enum_from_name :: proc($EnumType: typeid, name: string) -> (value: EnumType, ok: bool) {
+    ti := type_info_base(type_info_of(EnumType));
+    if eti, eti_ok := ti.variant.(runtime.Type_Info_Enum); eti_ok {
+        for value_name, i in eti.names {
+            if value_name != name do continue;
+            value_union := eti.values[i];
+            switch v in value_union {
+            case rune: value = EnumType(v); ok = true;
+            case u8:   value = EnumType(v); ok = true;
+            case u16:  value = EnumType(v); ok = true;
+            case u32:  value = EnumType(v); ok = true;
+            case u64:  value = EnumType(v); ok = true;
+            case uint: value = EnumType(v); ok = true;
+            case uintptr: value = EnumType(v); ok = true;
+            case i8:   value = EnumType(v); ok = true;
+            case i16:  value = EnumType(v); ok = true;
+            case i32:  value = EnumType(v); ok = true;
+            case i64:  value = EnumType(v); ok = true;
+            case int:  value = EnumType(v); ok = true;
+            }
+        }
+    } else {
+        panic("expected enum type to reflect.enum_from_name");
+    }
+    return;
+}
+
 union_variant_type_info :: proc(a: any) -> ^runtime.Type_Info {
 	id := union_variant_typeid(a);
 	return type_info_of(id);