`package reflect`; fix substring type bug; fix scoping rules for `using` on procedure parameter

2 files changed, 292 insertions, 4 deletions

diff --git a/core/reflect/reflect.odin b/core/reflect/reflect.odin
new file mode 100644
index 000000000..ecc2e7362
--- /dev/null
+++ b/core/reflect/reflect.odin
@@ -0,0 +1,285 @@
+package reflect
+
+import "core:runtime"
+import "core:mem"
+
+
+Type_Kind :: enum {
+	Invalid,
+
+	Named,
+	Integer,
+	Rune,
+	Float,
+	Complex,
+	String,
+	Boolean,
+	Any,
+	Type_Id,
+	Pointer,
+	Procedure,
+	Array,
+	Dynamic_Array,
+	Slice,
+	Tuple,
+	Struct,
+	Union,
+	Enum,
+	Map,
+	Bit_Field,
+	Bit_Set,
+	Opaque,
+	Simd_Vector,
+}
+
+
+type_kind :: proc(T: typeid) -> Type_Kind {
+	ti := type_info_of(T);
+	if ti != nil {
+		#complete switch _ in ti.variant {
+		case runtime.Type_Info_Named:         return .Named;
+		case runtime.Type_Info_Integer:       return .Integer;
+		case runtime.Type_Info_Rune:          return .Rune;
+		case runtime.Type_Info_Float:         return .Float;
+		case runtime.Type_Info_Complex:       return .Complex;
+		case runtime.Type_Info_String:        return .String;
+		case runtime.Type_Info_Boolean:       return .Boolean;
+		case runtime.Type_Info_Any:           return .Any;
+		case runtime.Type_Info_Type_Id:       return .Type_Id;
+		case runtime.Type_Info_Pointer:       return .Pointer;
+		case runtime.Type_Info_Procedure:     return .Procedure;
+		case runtime.Type_Info_Array:         return .Array;
+		case runtime.Type_Info_Dynamic_Array: return .Dynamic_Array;
+		case runtime.Type_Info_Slice:         return .Slice;
+		case runtime.Type_Info_Tuple:         return .Tuple;
+		case runtime.Type_Info_Struct:        return .Struct;
+		case runtime.Type_Info_Union:         return .Union;
+		case runtime.Type_Info_Enum:          return .Enum;
+		case runtime.Type_Info_Map:           return .Map;
+		case runtime.Type_Info_Bit_Field:     return .Bit_Field;
+		case runtime.Type_Info_Bit_Set:       return .Bit_Set;
+		case runtime.Type_Info_Opaque:        return .Opaque;
+		case runtime.Type_Info_Simd_Vector:   return .Simd_Vector;
+		}
+
+	}
+	return .Invalid;
+}
+
+// TODO(bill): Better name
+underlying_type_kind :: proc(T: typeid) -> Type_Kind {
+	return type_kind(runtime.typeid_base(T));
+}
+
+// TODO(bill): Better name
+backing_type_kind :: proc(T: typeid) -> Type_Kind {
+	return type_kind(runtime.typeid_core(T));
+}
+
+
+
+size_of_typeid :: proc(T: typeid) -> int {
+	if ti := type_info_of(T); ti != nil {
+		return ti.size;
+	}
+	return 0;
+}
+
+align_of_typeid :: proc(T: typeid) -> int {
+	if ti := type_info_of(T); ti != nil {
+		return ti.align;
+	}
+	return 1;
+}
+
+to_bytes :: proc(v: any) -> []byte {
+	if v != nil {
+		sz := size_of_typeid(v.id);
+		return mem.slice_ptr((^byte)(v.data), sz);
+	}
+	return nil;
+}
+
+any_data :: inline proc(v: any) -> (data: rawptr, id: typeid) {
+	return v.data, v.id;
+}
+
+is_nil :: proc(v: any) -> bool {
+	data := to_bytes(v);
+	if data != nil {
+		return true;
+	}
+	for v in data do if v != 0 {
+		return false;
+	}
+	return true;
+}
+
+
+index :: proc(v: any, i: int, loc := #caller_location) -> any {
+	if v == nil do return nil;
+
+	v := v;
+	v.id = runtime.typeid_base(v.id);
+	switch a in v {
+	case runtime.Type_Info_Array:
+		runtime.bounds_check_error_loc(loc, i, a.count);
+		offset := uintptr(a.elem.size * i);
+		data := rawptr(uintptr(v.data) + offset);
+		return any{data, a.elem.id};
+
+	case runtime.Type_Info_Slice:
+		raw := (^mem.Raw_Slice)(v.data);
+		runtime.bounds_check_error_loc(loc, i, raw.len);
+		offset := uintptr(a.elem.size * i);
+		data := rawptr(uintptr(raw.data) + offset);
+		return any{data, a.elem.id};
+
+	case runtime.Type_Info_Dynamic_Array:
+		raw := (^mem.Raw_Dynamic_Array)(v.data);
+		runtime.bounds_check_error_loc(loc, i, raw.len);
+		offset := uintptr(a.elem.size * i);
+		data := rawptr(uintptr(raw.data) + offset);
+		return any{data, a.elem.id};
+
+	case runtime.Type_Info_String:
+		if a.is_cstring do return nil;
+
+		raw := (^mem.Raw_String)(v.data);
+		runtime.bounds_check_error_loc(loc, i, raw.len);
+		offset := uintptr(size_of(u8) * i);
+		data := rawptr(uintptr(raw.data) + offset);
+		return any{data, typeid_of(u8)};
+	}
+	return nil;
+}
+
+
+
+
+Struct_Tag :: distinct string;
+
+Struct_Field :: struct {
+	name:   string,
+	type:   typeid,
+	tag:    Struct_Tag,
+	offset: uintptr,
+}
+
+struct_field_at :: proc(T: typeid, i: int) -> (field: Struct_Field) {
+	ti := runtime.type_info_base(type_info_of(T));
+	if s, ok := ti.variant.(runtime.Type_Info_Struct); ok {
+		if 0 <= i && i < len(s.names) {
+			field.name   = s.names[i];
+			field.type   = s.types[i].id;
+			field.tag    = Struct_Tag(s.tags[i]);
+			field.offset = s.offsets[i];
+		}
+	}
+	return;
+}
+
+struct_field_by_name :: proc(T: typeid, name: string) -> (field: Struct_Field) {
+	ti := runtime.type_info_base(type_info_of(T));
+	if s, ok := ti.variant.(runtime.Type_Info_Struct); ok {
+		for fname, i in s.names {
+			if fname == name {
+				field.name   = s.names[i];
+				field.type   = s.types[i].id;
+				field.tag    = Struct_Tag(s.tags[i]);
+				field.offset = s.offsets[i];
+				break;
+			}
+		}
+	}
+	return;
+}
+
+
+
+struct_field_names :: proc(T: typeid) -> []string {
+	ti := runtime.type_info_base(type_info_of(T));
+	if s, ok := ti.variant.(runtime.Type_Info_Struct); ok {
+		return s.names;
+	}
+	return nil;
+}
+
+struct_field_types :: proc(T: typeid) -> []^runtime.Type_Info {
+	ti := runtime.type_info_base(type_info_of(T));
+	if s, ok := ti.variant.(runtime.Type_Info_Struct); ok {
+		return s.types;
+	}
+	return nil;
+}
+
+
+struct_field_tags :: proc(T: typeid) -> []Struct_Tag {
+	ti := runtime.type_info_base(type_info_of(T));
+	if s, ok := ti.variant.(runtime.Type_Info_Struct); ok {
+		return transmute([]Struct_Tag)s.tags;
+	}
+	return nil;
+}
+
+struct_field_offsets :: proc(T: typeid) -> []uintptr {
+	ti := runtime.type_info_base(type_info_of(T));
+	if s, ok := ti.variant.(runtime.Type_Info_Struct); ok {
+		return s.offsets;
+	}
+	return nil;
+}
+
+
+
+struct_tag_get :: proc(tag: Struct_Tag, key: string) -> (value: string) {
+	value, _ = struct_tag_lookup(tag, key);
+	return;
+}
+
+struct_tag_lookup :: proc(tag: Struct_Tag, key: string) -> (value: string, ok: bool) {
+	for tag := tag; tag != ""; /**/ {
+		i := 0;
+		for i < len(tag) && tag[i] == ' ' { // Skip whitespace
+			i += 1;
+		}
+		tag = tag[i:];
+		if len(tag) == 0 do break;
+
+		i = 0;
+		loop: for i < len(tag) {
+			switch tag[i] {
+			case ':', '"':
+				break loop;
+			case 0x00 ..< ' ', 0x7f .. 0x9f: // break if control character is found
+				break loop;
+			}
+			i += 1;
+		}
+
+		if i == 0 do break;
+		if i+1 >= len(tag) do break;
+
+		if tag[i] != ':' || tag[i+1] != '"' {
+			break;
+		}
+		name := string(tag[:i]);
+		tag = tag[i+1:];
+
+		i = 1;
+		for i < len(tag) && tag[i] != '"' { // find closing quote
+			if tag[i] == '\\' do i += 1; // Skip escaped characters
+			i += 1;
+		}
+
+		if i >= len(tag) do break;
+
+		val := string(tag[:i+1]);
+		tag = tag[i+1:];
+
+		if key == name {
+			return val[1:i], true;
+		}
+	}
+	return;
+}
diff --git a/core/runtime/core.odin b/core/runtime/core.odin
index 28767cc2d..047281b10 100644
--- a/core/runtime/core.odin
+++ b/core/runtime/core.odin
@@ -283,19 +283,21 @@ type_info_base :: proc "contextless" (info: ^Type_Info) -> ^Type_Info {
 }
 
 
-type_info_base_without_enum :: proc "contextless" (info: ^Type_Info) -> ^Type_Info {
+type_info_core :: proc "contextless" (info: ^Type_Info) -> ^Type_Info {
 	if info == nil do return nil;
 
 	base := info;
 	loop: for {
 		switch i in base.variant {
-		case Type_Info_Named: base = i.base;
-		case Type_Info_Enum:  base = i.base;
+		case Type_Info_Named:  base = i.base;
+		case Type_Info_Enum:   base = i.base;
+		case Type_Info_Opaque: base = i.elem;
 		case: break loop;
 		}
 	}
 	return base;
 }
+type_info_base_without_enum :: type_info_core;
 
 __type_info_of :: proc "contextless" (id: typeid) -> ^Type_Info {
 	data := transmute(Typeid_Bit_Field)id;
@@ -311,10 +313,11 @@ typeid_base :: proc "contextless" (id: typeid) -> typeid {
 	ti = type_info_base(ti);
 	return ti.id;
 }
-typeid_base_without_enum :: proc "contextless" (id: typeid) -> typeid {
+typeid_core :: proc "contextless" (id: typeid) -> typeid {
 	ti := type_info_base_without_enum(type_info_of(id));
 	return ti.id;
 }
+typeid_base_without_enum :: typeid_core;