Merge pull request #1476 from odin-lang/odin-ast-changes

Replace `any` with `union` for subtyping in `core:odin/ast`

6 files changed, 595 insertions, 340 deletions

diff --git a/core/odin/ast/ast.odin b/core/odin/ast/ast.odin
index 8eb0def44..740299539 100644
--- a/core/odin/ast/ast.odin
+++ b/core/odin/ast/ast.odin
@@ -34,7 +34,7 @@ Node :: struct {
 	pos:         tokenizer.Pos,
 	end:         tokenizer.Pos,
 	state_flags: Node_State_Flags,
-	derived:     any,
+	derived:     Any_Node,
 }
 
 Comment_Group :: struct {
@@ -88,9 +88,11 @@ File :: struct {
 
 Expr :: struct {
 	using expr_base: Node,
+	derived_expr: Any_Expr,
 }
 Stmt :: struct {
 	using stmt_base: Node,
+	derived_stmt: Any_Stmt,
 }
 Decl :: struct {
 	using decl_base: Stmt,
@@ -541,7 +543,7 @@ unparen_expr :: proc(expr: ^Expr) -> (val: ^Expr) {
 		return
 	}
 	for {
-		e, ok := val.derived.(Paren_Expr)
+		e, ok := val.derived.(^Paren_Expr)
 		if !ok || e.expr == nil {
 			break
 		}
@@ -758,4 +760,173 @@ Matrix_Type :: struct {
 	row_count:    ^Expr,
 	column_count: ^Expr,
 	elem:         ^Expr,
-}
\ No newline at end of file
+}
+
+
+Any_Node :: union {
+	^Package,
+	^File,
+	^Comment_Group,
+
+	^Bad_Expr,
+	^Ident,
+	^Implicit,
+	^Undef,
+	^Basic_Lit,
+	^Basic_Directive,
+	^Ellipsis,
+	^Proc_Lit,
+	^Comp_Lit,
+	^Tag_Expr,
+	^Unary_Expr,
+	^Binary_Expr,
+	^Paren_Expr,
+	^Selector_Expr,
+	^Implicit_Selector_Expr,
+	^Selector_Call_Expr,
+	^Index_Expr,
+	^Deref_Expr,
+	^Slice_Expr,
+	^Matrix_Index_Expr,
+	^Call_Expr,
+	^Field_Value,
+	^Ternary_If_Expr,
+	^Ternary_When_Expr,
+	^Or_Else_Expr,
+	^Or_Return_Expr,
+	^Type_Assertion,
+	^Type_Cast,
+	^Auto_Cast,
+	^Inline_Asm_Expr,
+
+	^Proc_Group,
+
+	^Typeid_Type,
+	^Helper_Type,
+	^Distinct_Type,
+	^Poly_Type,
+	^Proc_Type,
+	^Pointer_Type,
+	^Multi_Pointer_Type,
+	^Array_Type,
+	^Dynamic_Array_Type,
+	^Struct_Type,
+	^Union_Type,
+	^Enum_Type,
+	^Bit_Set_Type,
+	^Map_Type,
+	^Relative_Type,
+	^Matrix_Type,
+
+	^Bad_Stmt,
+	^Empty_Stmt,
+	^Expr_Stmt,
+	^Tag_Stmt,
+	^Assign_Stmt,
+	^Block_Stmt,
+	^If_Stmt,
+	^When_Stmt,
+	^Return_Stmt,
+	^Defer_Stmt,
+	^For_Stmt,
+	^Range_Stmt,
+	^Inline_Range_Stmt,
+	^Case_Clause,
+	^Switch_Stmt,
+	^Type_Switch_Stmt,
+	^Branch_Stmt,
+	^Using_Stmt,
+
+	^Bad_Decl,
+	^Value_Decl,
+	^Package_Decl,
+	^Import_Decl,
+	^Foreign_Block_Decl,
+	^Foreign_Import_Decl,
+
+	^Attribute,
+	^Field,
+	^Field_List,
+}
+
+
+Any_Expr :: union {
+	^Bad_Expr,
+	^Ident,
+	^Implicit,
+	^Undef,
+	^Basic_Lit,
+	^Basic_Directive,
+	^Ellipsis,
+	^Proc_Lit,
+	^Comp_Lit,
+	^Tag_Expr,
+	^Unary_Expr,
+	^Binary_Expr,
+	^Paren_Expr,
+	^Selector_Expr,
+	^Implicit_Selector_Expr,
+	^Selector_Call_Expr,
+	^Index_Expr,
+	^Deref_Expr,
+	^Slice_Expr,
+	^Matrix_Index_Expr,
+	^Call_Expr,
+	^Field_Value,
+	^Ternary_If_Expr,
+	^Ternary_When_Expr,
+	^Or_Else_Expr,
+	^Or_Return_Expr,
+	^Type_Assertion,
+	^Type_Cast,
+	^Auto_Cast,
+	^Inline_Asm_Expr,
+
+	^Proc_Group,
+
+	^Typeid_Type,
+	^Helper_Type,
+	^Distinct_Type,
+	^Poly_Type,
+	^Proc_Type,
+	^Pointer_Type,
+	^Multi_Pointer_Type,
+	^Array_Type,
+	^Dynamic_Array_Type,
+	^Struct_Type,
+	^Union_Type,
+	^Enum_Type,
+	^Bit_Set_Type,
+	^Map_Type,
+	^Relative_Type,
+	^Matrix_Type,
+}
+
+
+Any_Stmt :: union {
+	^Bad_Stmt,
+	^Empty_Stmt,
+	^Expr_Stmt,
+	^Tag_Stmt,
+	^Assign_Stmt,
+	^Block_Stmt,
+	^If_Stmt,
+	^When_Stmt,
+	^Return_Stmt,
+	^Defer_Stmt,
+	^For_Stmt,
+	^Range_Stmt,
+	^Inline_Range_Stmt,
+	^Case_Clause,
+	^Switch_Stmt,
+	^Type_Switch_Stmt,
+	^Branch_Stmt,
+	^Using_Stmt,
+
+	^Bad_Decl,
+	^Value_Decl,
+	^Package_Decl,
+	^Import_Decl,
+	^Foreign_Block_Decl,
+	^Foreign_Import_Decl,
+}
diff --git a/core/odin/ast/clone.odin b/core/odin/ast/clone.odin
index 1e3058678..400c064f5 100644
--- a/core/odin/ast/clone.odin
+++ b/core/odin/ast/clone.odin
@@ -1,16 +1,25 @@
 package odin_ast
 
+import "core:intrinsics"
 import "core:mem"
 import "core:fmt"
+import "core:reflect"
 import "core:odin/tokenizer"
+_ :: intrinsics
 
 new :: proc($T: typeid, pos, end: tokenizer.Pos) -> ^T {
 	n, _ := mem.new(T)
 	n.pos = pos
 	n.end = end
-	n.derived = n^
+	n.derived = n
 	base: ^Node = n // dummy check
 	_ = base // "Use" type to make -vet happy
+	when intrinsics.type_has_field(T, "derived_expr") {
+		n.derived_expr = n
+	}
+	when intrinsics.type_has_field(T, "derived_stmt") {
+		n.derived_stmt = n
+	}
 	return n
 }
 
@@ -59,232 +68,257 @@ clone_node :: proc(node: ^Node) -> ^Node {
 		return nil
 	}
 
-	size := size_of(Node)
+	size  := size_of(Node)
 	align := align_of(Node)
-	ti := type_info_of(node.derived.id)
+	ti := reflect.union_variant_type_info(node.derived)
 	if ti != nil {
-		size = ti.size
-		align = ti.align
+		elem := ti.variant.(reflect.Type_Info_Pointer).elem
+		size  = elem.size
+		align = elem.align
 	}
 
-	switch in node.derived {
-	case Package, File:
+	#partial switch in node.derived {
+	case ^Package, ^File:
 		panic("Cannot clone this node type")
 	}
 
 	res := cast(^Node)mem.alloc(size, align)
 	src: rawptr = node
 	if node.derived != nil {
-		src = node.derived.data
+		src = (^rawptr)(&node.derived)^
 	}
 	mem.copy(res, src, size)
-	res.derived.data = rawptr(res)
-	res.derived.id = node.derived.id
+	res_ptr_any: any
+	res_ptr_any.data = &res
+	res_ptr_any.id = ti.id
+
+	reflect.set_union_value(res.derived, res_ptr_any)
 
-	switch r in &res.derived {
-	case Bad_Expr:
-	case Ident:
-	case Implicit:
-	case Undef:
-	case Basic_Lit:
+	res_ptr := reflect.deref(res_ptr_any)
+
+	if de := reflect.struct_field_value_by_name(res_ptr, "derived_expr", true); de != nil {
+		reflect.set_union_value(de, res_ptr_any)
+	}
+	if ds := reflect.struct_field_value_by_name(res_ptr, "derived_stmt", true); ds != nil {
+		reflect.set_union_value(ds, res_ptr_any)
+	}
 
-	case Ellipsis:
+	if res.derived != nil do switch r in res.derived {
+	case ^Package, ^File:
+	case ^Bad_Expr:
+	case ^Ident:
+	case ^Implicit:
+	case ^Undef:
+	case ^Basic_Lit:
+	case ^Basic_Directive:
+	case ^Comment_Group:
+
+	case ^Ellipsis:
 		r.expr = clone(r.expr)
-	case Proc_Lit:
+	case ^Proc_Lit:
 		r.type = auto_cast clone(r.type)
 		r.body = clone(r.body)
-	case Comp_Lit:
+	case ^Comp_Lit:
 		r.type  = clone(r.type)
 		r.elems = clone(r.elems)
 
-	case Tag_Expr:
+	case ^Tag_Expr:
 		r.expr = clone(r.expr)
-	case Unary_Expr:
+	case ^Unary_Expr:
 		r.expr = clone(r.expr)
-	case Binary_Expr:
+	case ^Binary_Expr:
 		r.left  = clone(r.left)
 		r.right = clone(r.right)
-	case Paren_Expr:
+	case ^Paren_Expr:
 		r.expr = clone(r.expr)
-	case Selector_Expr:
+	case ^Selector_Expr:
 		r.expr = clone(r.expr)
 		r.field = auto_cast clone(r.field)
-	case Implicit_Selector_Expr:
+	case ^Implicit_Selector_Expr:
 		r.field = auto_cast clone(r.field)
-	case Selector_Call_Expr:
+	case ^Selector_Call_Expr:
 		r.expr = clone(r.expr)
 		r.call = auto_cast clone(r.call)
-	case Index_Expr:
+	case ^Index_Expr:
 		r.expr = clone(r.expr)
 		r.index = clone(r.index)
-	case Matrix_Index_Expr:
+	case ^Matrix_Index_Expr:
 		r.expr = clone(r.expr)
 		r.row_index = clone(r.row_index)
 		r.column_index = clone(r.column_index)
-	case Deref_Expr:
+	case ^Deref_Expr:
 		r.expr = clone(r.expr)
-	case Slice_Expr:
+	case ^Slice_Expr:
 		r.expr = clone(r.expr)
 		r.low  = clone(r.low)
 		r.high = clone(r.high)
-	case Call_Expr:
+	case ^Call_Expr:
 		r.expr = clone(r.expr)
 		r.args = clone(r.args)
-	case Field_Value:
+	case ^Field_Value:
 		r.field = clone(r.field)
 		r.value = clone(r.value)
-	case Ternary_If_Expr:
+	case ^Ternary_If_Expr:
 		r.x    = clone(r.x)
 		r.cond = clone(r.cond)
 		r.y    = clone(r.y)
-	case Ternary_When_Expr:
+	case ^Ternary_When_Expr:
 		r.x    = clone(r.x)
 		r.cond = clone(r.cond)
 		r.y    = clone(r.y)
-	case Or_Else_Expr:
+	case ^Or_Else_Expr:
 		r.x    = clone(r.x)
 		r.y    = clone(r.y)
-	case Or_Return_Expr:
+	case ^Or_Return_Expr:
 		r.expr = clone(r.expr)
-	case Type_Assertion:
+	case ^Type_Assertion:
 		r.expr = clone(r.expr)
 		r.type = clone(r.type)
-	case Type_Cast:
+	case ^Type_Cast:
 		r.type = clone(r.type)
 		r.expr = clone(r.expr)
-	case Auto_Cast:
+	case ^Auto_Cast:
 		r.expr = clone(r.expr)
-	case Inline_Asm_Expr:
+	case ^Inline_Asm_Expr:
 		r.param_types        = clone(r.param_types)
 		r.return_type        = clone(r.return_type)
 		r.constraints_string = clone(r.constraints_string)
 		r.asm_string         = clone(r.asm_string)
 
-	case Bad_Stmt:
+	case ^Bad_Stmt:
 		// empty
-	case Empty_Stmt:
+	case ^Empty_Stmt:
 		// empty
-	case Expr_Stmt:
+	case ^Expr_Stmt:
 		r.expr = clone(r.expr)
-	case Tag_Stmt:
+	case ^Tag_Stmt:
 		r.stmt = clone(r.stmt)
 
-	case Assign_Stmt:
+	case ^Assign_Stmt:
 		r.lhs = clone(r.lhs)
 		r.rhs = clone(r.rhs)
-	case Block_Stmt:
+	case ^Block_Stmt:
 		r.label = clone(r.label)
 		r.stmts = clone(r.stmts)
-	case If_Stmt:
+	case ^If_Stmt:
 		r.label     = clone(r.label)
 		r.init      = clone(r.init)
 		r.cond      = clone(r.cond)
 		r.body      = clone(r.body)
 		r.else_stmt = clone(r.else_stmt)
-	case When_Stmt:
+	case ^When_Stmt:
 		r.cond      = clone(r.cond)
 		r.body      = clone(r.body)
 		r.else_stmt = clone(r.else_stmt)
-	case Return_Stmt:
+	case ^Return_Stmt:
 		r.results = clone(r.results)
-	case Defer_Stmt:
+	case ^Defer_Stmt:
 		r.stmt = clone(r.stmt)
-	case For_Stmt:
+	case ^For_Stmt:
 		r.label = clone(r.label)
 		r.init = clone(r.init)
 		r.cond = clone(r.cond)
 		r.post = clone(r.post)
 		r.body = clone(r.body)
-	case Range_Stmt:
+	case ^Range_Stmt:
 		r.label = clone(r.label)
 		r.vals = clone(r.vals)
 		r.expr = clone(r.expr)
 		r.body = clone(r.body)
-	case Case_Clause:
+	case ^Inline_Range_Stmt:
+		r.label = clone(r.label)
+		r.val0 = clone(r.val0)
+		r.val1 = clone(r.val1)
+		r.expr = clone(r.expr)
+		r.body = clone(r.body)
+	case ^Case_Clause:
 		r.list = clone(r.list)
 		r.body = clone(r.body)
-	case Switch_Stmt:
+	case ^Switch_Stmt:
 		r.label = clone(r.label)
 		r.init = clone(r.init)
 		r.cond = clone(r.cond)
 		r.body = clone(r.body)
-	case Type_Switch_Stmt:
+	case ^Type_Switch_Stmt:
 		r.label = clone(r.label)
 		r.tag  = clone(r.tag)
 		r.expr = clone(r.expr)
 		r.body = clone(r.body)
-	case Branch_Stmt:
+	case ^Branch_Stmt:
 		r.label = auto_cast clone(r.label)
-	case Using_Stmt:
+	case ^Using_Stmt:
 		r.list = clone(r.list)
-	case Bad_Decl:
-	case Value_Decl:
+	case ^Bad_Decl:
+	case ^Value_Decl:
 		r.attributes = clone(r.attributes)
 		r.names      = clone(r.names)
 		r.type       = clone(r.type)
 		r.values     = clone(r.values)
-	case Package_Decl:
-	case Import_Decl:
-	case Foreign_Block_Decl:
+	case ^Package_Decl:
+	case ^Import_Decl:
+	case ^Foreign_Block_Decl:
 		r.attributes      = clone(r.attributes)
 		r.foreign_library = clone(r.foreign_library)
 		r.body            = clone(r.body)
-	case Foreign_Import_Decl:
+	case ^Foreign_Import_Decl:
 		r.name = auto_cast clone(r.name)
-	case Proc_Group:
+	case ^Proc_Group:
 		r.args = clone(r.args)
-	case Attribute:
+	case ^Attribute:
 		r.elems = clone(r.elems)
-	case Field:
+	case ^Field:
 		r.names         = clone(r.names)
 		r.type          = clone(r.type)
 		r.default_value = clone(r.default_value)
-	case Field_List:
+	case ^Field_List:
 		r.list = clone(r.list)
-	case Typeid_Type:
+	case ^Typeid_Type:
 		r.specialization = clone(r.specialization)
-	case Helper_Type:
+	case ^Helper_Type:
 		r.type = clone(r.type)
-	case Distinct_Type:
+	case ^Distinct_Type:
 		r.type = clone(r.type)
-	case Poly_Type:
+	case ^Poly_Type:
 		r.type = auto_cast clone(r.type)
 		r.specialization = clone(r.specialization)
-	case Proc_Type:
+	case ^Proc_Type:
 		r.params  = auto_cast clone(r.params)
 		r.results = auto_cast clone(r.results)
-	case Pointer_Type:
+	case ^Pointer_Type:
 		r.elem = clone(r.elem)
-	case Multi_Pointer_Type:
+	case ^Multi_Pointer_Type:
 		r.elem = clone(r.elem)
-	case Array_Type:
+	case ^Array_Type:
 		r.len  = clone(r.len)
 		r.elem = clone(r.elem)
-	case Dynamic_Array_Type:
+	case ^Dynamic_Array_Type:
 		r.elem = clone(r.elem)
-	case Struct_Type:
+	case ^Struct_Type:
 		r.poly_params = auto_cast clone(r.poly_params)
 		r.align = clone(r.align)
 		r.fields = auto_cast clone(r.fields)
-	case Union_Type:
+	case ^Union_Type:
 		r.poly_params = auto_cast clone(r.poly_params)
 		r.align = clone(r.align)
 		r.variants = clone(r.variants)
-	case Enum_Type:
+	case ^Enum_Type:
 		r.base_type = clone(r.base_type)
 		r.fields = clone(r.fields)
-	case Bit_Set_Type:
+	case ^Bit_Set_Type:
 		r.elem = clone(r.elem)
 		r.underlying = clone(r.underlying)
-	case Map_Type:
+	case ^Map_Type:
 		r.key = clone(r.key)
 		r.value = clone(r.value)
-	case Matrix_Type:
+	case ^Matrix_Type:
 		r.row_count = clone(r.row_count)
 		r.column_count = clone(r.column_count)
 		r.elem = clone(r.elem)
+	case ^Relative_Type:
+		r.tag = clone(r.tag)
+		r.type = clone(r.type)
 	case:
-		fmt.panicf("Unhandled node kind: %T", r)
+		fmt.panicf("Unhandled node kind: %v", r)
 	}
 
 	return res
diff --git a/core/odin/ast/walk.odin b/core/odin/ast/walk.odin
index d0d17cc9e..7241d283f 100644
--- a/core/odin/ast/walk.odin
+++ b/core/odin/ast/walk.odin
@@ -59,64 +59,64 @@ walk :: proc(v: ^Visitor, node: ^Node) {
 	}
 
 	switch n in &node.derived {
-	case File:
+	case ^File:
 		if n.docs != nil {
 			walk(v, n.docs)
 		}
 		walk_stmt_list(v, n.decls[:])
-	case Package:
+	case ^Package:
 		for _, f in n.files {
 			walk(v, f)
 		}
 
-	case Comment_Group:
+	case ^Comment_Group:
 		// empty
-	case Bad_Expr:
-	case Ident:
-	case Implicit:
-	case Undef:
-	case Basic_Lit:
-	case Basic_Directive:
-	case Ellipsis:
+	case ^Bad_Expr:
+	case ^Ident:
+	case ^Implicit:
+	case ^Undef:
+	case ^Basic_Lit:
+	case ^Basic_Directive:
+	case ^Ellipsis:
 		if n.expr != nil {
 			walk(v, n.expr)
 		}
-	case Proc_Lit:
+	case ^Proc_Lit:
 		walk(v, n.type)
 		walk(v, n.body)
 		walk_expr_list(v, n.where_clauses)
-	case Comp_Lit:
+	case ^Comp_Lit:
 		if n.type != nil {
 			walk(v, n.type)
 		}
 		walk_expr_list(v, n.elems)
-	case Tag_Expr:
+	case ^Tag_Expr:
 		walk(v, n.expr)
-	case Unary_Expr:
+	case ^Unary_Expr:
 		walk(v, n.expr)
-	case Binary_Expr:
+	case ^Binary_Expr:
 		walk(v, n.left)
 		walk(v, n.right)
-	case Paren_Expr:
+	case ^Paren_Expr:
 		walk(v, n.expr)
-	case Selector_Expr:
+	case ^Selector_Expr:
 		walk(v, n.expr)
 		walk(v, n.field)
-	case Implicit_Selector_Expr:
+	case ^Implicit_Selector_Expr:
 		walk(v, n.field)
-	case Selector_Call_Expr:
+	case ^Selector_Call_Expr:
 		walk(v, n.expr)
 		walk(v, n.call)
-	case Index_Expr:
+	case ^Index_Expr:
 		walk(v, n.expr)
 		walk(v, n.index)
-	case Matrix_Index_Expr:
+	case ^Matrix_Index_Expr:
 		walk(v, n.expr)
 		walk(v, n.row_index)
 		walk(v, n.column_index)
-	case Deref_Expr:
+	case ^Deref_Expr:
 		walk(v, n.expr)
-	case Slice_Expr:
+	case ^Slice_Expr:
 		walk(v, n.expr)
 		if n.low != nil {
 			walk(v, n.low)
@@ -124,57 +124,57 @@ walk :: proc(v: ^Visitor, node: ^Node) {
 		if n.high != nil {
 			walk(v, n.high)
 		}
-	case Call_Expr:
+	case ^Call_Expr:
 		walk(v, n.expr)
 		walk_expr_list(v, n.args)
-	case Field_Value:
+	case ^Field_Value:
 		walk(v, n.field)
 		walk(v, n.value)
-	case Ternary_If_Expr:
+	case ^Ternary_If_Expr:
 		walk(v, n.x)
 		walk(v, n.cond)
 		walk(v, n.y)
-	case Ternary_When_Expr:
+	case ^Ternary_When_Expr:
 		walk(v, n.x)
 		walk(v, n.cond)
 		walk(v, n.y)
-	case Or_Else_Expr:
+	case ^Or_Else_Expr:
 		walk(v, n.x)
 		walk(v, n.y)
-	case Or_Return_Expr:
+	case ^Or_Return_Expr:
 		walk(v, n.expr)
-	case Type_Assertion:
+	case ^Type_Assertion:
 		walk(v, n.expr)
 		if n.type != nil {
 			walk(v, n.type)
 		}
-	case Type_Cast:
+	case ^Type_Cast:
 		walk(v, n.type)
 		walk(v, n.expr)
-	case Auto_Cast:
+	case ^Auto_Cast:
 		walk(v, n.expr)
-	case Inline_Asm_Expr:
+	case ^Inline_Asm_Expr:
 		walk_expr_list(v, n.param_types)
 		walk(v, n.return_type)
 		walk(v, n.constraints_string)
 		walk(v, n.asm_string)
 
 
-	case Bad_Stmt:
-	case Empty_Stmt:
-	case Expr_Stmt:
+	case ^Bad_Stmt:
+	case ^Empty_Stmt:
+	case ^Expr_Stmt:
 		walk(v, n.expr)
-	case Tag_Stmt:
+	case ^Tag_Stmt:
 		walk(v, n.stmt)
-	case Assign_Stmt:
+	case ^Assign_Stmt:
 		walk_expr_list(v, n.lhs)
 		walk_expr_list(v, n.rhs)
-	case Block_Stmt:
+	case ^Block_Stmt:
 		if n.label != nil {
 			walk(v, n.label)
 		}
 		walk_stmt_list(v, n.stmts)
-	case If_Stmt:
+	case ^If_Stmt:
 		if n.label != nil {
 			walk(v, n.label)
 		}
@@ -186,17 +186,17 @@ walk :: proc(v: ^Visitor, node: ^Node) {
 		if n.else_stmt != nil {
 			walk(v, n.else_stmt)
 		}
-	case When_Stmt:
+	case ^When_Stmt:
 		walk(v, n.cond)
 		walk(v, n.body)
 		if n.else_stmt != nil {
 			walk(v, n.else_stmt)
 		}
-	case Return_Stmt:
+	case ^Return_Stmt:
 		walk_expr_list(v, n.results)
-	case Defer_Stmt:
+	case ^Defer_Stmt:
 		walk(v, n.stmt)
-	case For_Stmt:
+	case ^For_Stmt:
 		if n.label != nil {
 			walk(v, n.label)
 		}
@@ -210,7 +210,7 @@ walk :: proc(v: ^Visitor, node: ^Node) {
 			walk(v, n.post)
 		}
 		walk(v, n.body)
-	case Range_Stmt:
+	case ^Range_Stmt:
 		if n.label != nil {
 			walk(v, n.label)
 		}
@@ -221,7 +221,7 @@ walk :: proc(v: ^Visitor, node: ^Node) {
 		}
 		walk(v, n.expr)
 		walk(v, n.body)
-	case Inline_Range_Stmt:
+	case ^Inline_Range_Stmt:
 		if n.label != nil {
 			walk(v, n.label)
 		}
@@ -233,10 +233,10 @@ walk :: proc(v: ^Visitor, node: ^Node) {
 		}
 		walk(v, n.expr)
 		walk(v, n.body)
-	case Case_Clause:
+	case ^Case_Clause:
 		walk_expr_list(v, n.list)
 		walk_stmt_list(v, n.body)
-	case Switch_Stmt:
+	case ^Switch_Stmt:
 		if n.label != nil {
 			walk(v, n.label)
 		}
@@ -247,7 +247,7 @@ walk :: proc(v: ^Visitor, node: ^Node) {
 			walk(v, n.cond)
 		}
 		walk(v, n.body)
-	case Type_Switch_Stmt:
+	case ^Type_Switch_Stmt:
 		if n.label != nil {
 			walk(v, n.label)
 		}
@@ -258,16 +258,16 @@ walk :: proc(v: ^Visitor, node: ^Node) {
 			walk(v, n.expr)
 		}
 		walk(v, n.body)
-	case Branch_Stmt:
+	case ^Branch_Stmt:
 		if n.label != nil {
 			walk(v, n.label)
 		}
-	case Using_Stmt:
+	case ^Using_Stmt:
 		walk_expr_list(v, n.list)
 
 
-	case Bad_Decl:
-	case Value_Decl:
+	case ^Bad_Decl:
+	case ^Value_Decl:
 		if n.docs != nil {
 			walk(v, n.docs)
 		}
@@ -280,21 +280,21 @@ walk :: proc(v: ^Visitor, node: ^Node) {
 		if n.comment != nil {
 			walk(v, n.comment)
 		}
-	case Package_Decl:
+	case ^Package_Decl:
 		if n.docs != nil {
 			walk(v, n.docs)
 		}
 		if n.comment != nil {
 			walk(v, n.comment)
 		}
-	case Import_Decl:
+	case ^Import_Decl:
 		if n.docs != nil {
 			walk(v, n.docs)
 		}
 		if n.comment != nil {
 			walk(v, n.comment)
 		}
-	case Foreign_Block_Decl:
+	case ^Foreign_Block_Decl:
 		if n.docs != nil {
 			walk(v, n.docs)
 		}
@@ -303,7 +303,7 @@ walk :: proc(v: ^Visitor, node: ^Node) {
 			walk(v, n.foreign_library)
 		}
 		walk(v, n.body)
-	case Foreign_Import_Decl:
+	case ^Foreign_Import_Decl:
 		if n.docs != nil {
 			walk(v, n.docs)
 		}
@@ -313,11 +313,11 @@ walk :: proc(v: ^Visitor, node: ^Node) {
 			walk(v, n.comment)
 		}
 
-	case Proc_Group:
+	case ^Proc_Group:
 		walk_expr_list(v, n.args)
-	case Attribute:
+	case ^Attribute:
 		walk_expr_list(v, n.elems)
-	case Field:
+	case ^Field:
 		if n.docs != nil {
 			walk(v, n.docs)
 		}
@@ -331,31 +331,31 @@ walk :: proc(v: ^Visitor, node: ^Node) {
 		if n.comment != nil {
 			walk(v, n.comment)
 		}
-	case Field_List:
+	case ^Field_List:
 		for x in n.list {
 			walk(v, x)
 		}
-	case Typeid_Type:
+	case ^Typeid_Type:
 		if n.specialization != nil {
 			walk(v, n.specialization)
 		}
-	case Helper_Type:
+	case ^Helper_Type:
 		walk(v, n.type)
-	case Distinct_Type:
+	case ^Distinct_Type:
 		walk(v, n.type)
-	case Poly_Type:
+	case ^Poly_Type:
 		walk(v, n.type)
 		if n.specialization != nil {
 			walk(v, n.specialization)
 		}
-	case Proc_Type:
+	case ^Proc_Type:
 		walk(v, n.params)
 		walk(v, n.results)
-	case Pointer_Type:
+	case ^Pointer_Type:
 		walk(v, n.elem)
-	case Multi_Pointer_Type:
+	case ^Multi_Pointer_Type:
 		walk(v, n.elem)
-	case Array_Type:
+	case ^Array_Type:
 		if n.tag != nil {
 			walk(v, n.tag)
 		}
@@ -363,12 +363,12 @@ walk :: proc(v: ^Visitor, node: ^Node) {
 			walk(v, n.len)
 		}
 		walk(v, n.elem)
-	case Dynamic_Array_Type:
+	case ^Dynamic_Array_Type:
 		if n.tag != nil {
 			walk(v, n.tag)
 		}
 		walk(v, n.elem)
-	case Struct_Type:
+	case ^Struct_Type:
 		if n.poly_params != nil {
 			walk(v, n.poly_params)
 		}
@@ -377,7 +377,7 @@ walk :: proc(v: ^Visitor, node: ^Node) {
 		}
 		walk_expr_list(v, n.where_clauses)
 		walk(v, n.fields)
-	case Union_Type:
+	case ^Union_Type:
 		if n.poly_params != nil {
 			walk(v, n.poly_params)
 		}
@@ -386,23 +386,23 @@ walk :: proc(v: ^Visitor, node: ^Node) {
 		}
 		walk_expr_list(v, n.where_clauses)
 		walk_expr_list(v, n.variants)
-	case Enum_Type:
+	case ^Enum_Type:
 		if n.base_type != nil {
 			walk(v, n.base_type)
 		}
 		walk_expr_list(v, n.fields)
-	case Bit_Set_Type:
+	case ^Bit_Set_Type:
 		walk(v, n.elem)
 		if n.underlying != nil {
 			walk(v, n.underlying)
 		}
-	case Map_Type:
+	case ^Map_Type:
 		walk(v, n.key)
 		walk(v, n.value)
-	case Relative_Type:
+	case ^Relative_Type:
 		walk(v, n.tag)
 		walk(v, n.type)
-	case Matrix_Type:
+	case ^Matrix_Type:
 		walk(v, n.row_count)
 		walk(v, n.column_count)
 		walk(v, n.elem)
diff --git a/core/odin/parser/parser.odin b/core/odin/parser/parser.odin
index cfd860bfa..1546dce2d 100644
--- a/core/odin/parser/parser.odin
+++ b/core/odin/parser/parser.odin
@@ -195,10 +195,10 @@ parse_file :: proc(p: ^Parser, file: ^ast.File) -> bool {
 	for p.curr_tok.kind != .EOF {
 		stmt := parse_stmt(p)
 		if stmt != nil {
-			if _, ok := stmt.derived.(ast.Empty_Stmt); !ok {
+			if _, ok := stmt.derived.(^ast.Empty_Stmt); !ok {
 				append(&p.file.decls, stmt)
-				if es, es_ok := stmt.derived.(ast.Expr_Stmt); es_ok && es.expr != nil {
-					if _, pl_ok := es.expr.derived.(ast.Proc_Lit); pl_ok {
+				if es, es_ok := stmt.derived.(^ast.Expr_Stmt); es_ok && es.expr != nil {
+					if _, pl_ok := es.expr.derived.(^ast.Proc_Lit); pl_ok {
 						error(p, stmt.pos, "procedure literal evaluated but not used")
 					}
 				}
@@ -459,7 +459,7 @@ is_blank_ident_token :: proc(tok: tokenizer.Token) -> bool {
 	return false
 }
 is_blank_ident_node :: proc(node: ^ast.Node) -> bool {
-	if ident, ok := node.derived.(ast.Ident); ok {
+	if ident, ok := node.derived.(^ast.Ident); ok {
 		return is_blank_ident(ident.name)
 	}
 	return true
@@ -502,34 +502,34 @@ is_semicolon_optional_for_node :: proc(p: ^Parser, node: ^ast.Node) -> bool {
 		return true
 	}
 
-	switch n in node.derived {
-	case ast.Empty_Stmt, ast.Block_Stmt:
+	#partial switch n in node.derived {
+	case ^ast.Empty_Stmt, ^ast.Block_Stmt:
 		return true
 
-	case ast.If_Stmt, ast.When_Stmt,
-	     ast.For_Stmt, ast.Range_Stmt, ast.Inline_Range_Stmt,
-	     ast.Switch_Stmt, ast.Type_Switch_Stmt:
+	case ^ast.If_Stmt, ^ast.When_Stmt,
+	     ^ast.For_Stmt, ^ast.Range_Stmt, ^ast.Inline_Range_Stmt,
+	     ^ast.Switch_Stmt, ^ast.Type_Switch_Stmt:
 		return true
 
-	case ast.Helper_Type:
+	case ^ast.Helper_Type:
 		return is_semicolon_optional_for_node(p, n.type)
-	case ast.Distinct_Type:
+	case ^ast.Distinct_Type:
 		return is_semicolon_optional_for_node(p, n.type)
-	case ast.Pointer_Type:
+	case ^ast.Pointer_Type:
 		return is_semicolon_optional_for_node(p, n.elem)
-	case ast.Struct_Type, ast.Union_Type, ast.Enum_Type:
+	case ^ast.Struct_Type, ^ast.Union_Type, ^ast.Enum_Type:
 		// Require semicolon within a procedure body
 		return p.curr_proc == nil
-	case ast.Proc_Lit:
+	case ^ast.Proc_Lit:
 		return true
 
-	case ast.Package_Decl, ast.Import_Decl, ast.Foreign_Import_Decl:
+	case ^ast.Package_Decl, ^ast.Import_Decl, ^ast.Foreign_Import_Decl:
 		return true
 
-	case ast.Foreign_Block_Decl:
+	case ^ast.Foreign_Block_Decl:
 		return is_semicolon_optional_for_node(p, n.body)
 
-	case ast.Value_Decl:
+	case ^ast.Value_Decl:
 		if n.is_mutable {
 			return false
 		}
@@ -641,10 +641,10 @@ parse_stmt_list :: proc(p: ^Parser) -> []^ast.Stmt {
 	    p.curr_tok.kind != .EOF  {
 		stmt := parse_stmt(p)
 		if stmt != nil {
-			if _, ok := stmt.derived.(ast.Empty_Stmt); !ok {
+			if _, ok := stmt.derived.(^ast.Empty_Stmt); !ok {
 				append(&list, stmt)
-				if es, es_ok := stmt.derived.(ast.Expr_Stmt); es_ok && es.expr != nil {
-					if _, pl_ok := es.expr.derived.(ast.Proc_Lit); pl_ok {
+				if es, es_ok := stmt.derived.(^ast.Expr_Stmt); es_ok && es.expr != nil {
+					if _, pl_ok := es.expr.derived.(^ast.Proc_Lit); pl_ok {
 						error(p, stmt.pos, "procedure literal evaluated but not used")
 					}
 				}
@@ -722,7 +722,7 @@ convert_stmt_to_expr :: proc(p: ^Parser, stmt: ^ast.Stmt, kind: string) -> ^ast.
 	if stmt == nil {
 		return nil
 	}
-	if es, ok := stmt.derived.(ast.Expr_Stmt); ok {
+	if es, ok := stmt.derived.(^ast.Expr_Stmt); ok {
 		return es.expr
 	}
 	error(p, stmt.pos, "expected %s, found a simple statement", kind)
@@ -864,7 +864,7 @@ parse_for_stmt :: proc(p: ^Parser) -> ^ast.Stmt {
 
 		if p.curr_tok.kind != .Semicolon {
 			cond = parse_simple_stmt(p, {Stmt_Allow_Flag.In})
-			if as, ok := cond.derived.(ast.Assign_Stmt); ok && as.op.kind == .In {
+			if as, ok := cond.derived.(^ast.Assign_Stmt); ok && as.op.kind == .In {
 				is_range = true
 			}
 		}
@@ -906,7 +906,7 @@ parse_for_stmt :: proc(p: ^Parser) -> ^ast.Stmt {
 
 
 	if is_range {
-		assign_stmt := cond.derived.(ast.Assign_Stmt)
+		assign_stmt := cond.derived.(^ast.Assign_Stmt)
 		vals := assign_stmt.lhs[:]
 
 		rhs: ^ast.Expr
@@ -987,7 +987,7 @@ parse_switch_stmt :: proc(p: ^Parser) -> ^ast.Stmt {
 			tag = as
 		} else {
 			tag = parse_simple_stmt(p, {Stmt_Allow_Flag.In})
-			if as, ok := tag.derived.(ast.Assign_Stmt); ok && as.op.kind == .In {
+			if as, ok := tag.derived.(^ast.Assign_Stmt); ok && as.op.kind == .In {
 				is_type_switch = true
 			} else if parse_control_statement_semicolon_separator(p) {
 				init = tag
@@ -1074,14 +1074,14 @@ parse_attribute :: proc(p: ^Parser, tok: tokenizer.Token, open_kind, close_kind:
 	skip_possible_newline(p)
 
 	decl := parse_stmt(p)
-	switch d in &decl.derived {
-	case ast.Value_Decl:
+	#partial switch d in decl.derived_stmt {
+	case ^ast.Value_Decl:
 		if d.docs == nil { d.docs = docs }
 		append(&d.attributes, attribute)
-	case ast.Foreign_Block_Decl:
+	case ^ast.Foreign_Block_Decl:
 		if d.docs == nil { d.docs = docs }
 		append(&d.attributes, attribute)
-	case ast.Foreign_Import_Decl:
+	case ^ast.Foreign_Import_Decl:
 		if d.docs == nil { d.docs = docs }
 		append(&d.attributes, attribute)
 	case:
@@ -1095,11 +1095,11 @@ parse_attribute :: proc(p: ^Parser, tok: tokenizer.Token, open_kind, close_kind:
 
 parse_foreign_block_decl :: proc(p: ^Parser) -> ^ast.Stmt {
 	decl := parse_stmt(p)
-	switch in decl.derived {
-	case ast.Empty_Stmt, ast.Bad_Stmt, ast.Bad_Decl:
+	#partial switch in decl.derived_stmt {
+	case ^ast.Empty_Stmt, ^ast.Bad_Stmt, ^ast.Bad_Decl:
 		// Ignore
 		return nil
-	case ast.When_Stmt, ast.Value_Decl:
+	case ^ast.When_Stmt, ^ast.Value_Decl:
 		return decl
 	}
 
@@ -1303,13 +1303,13 @@ parse_stmt :: proc(p: ^Parser) -> ^ast.Stmt {
 	case .Defer:
 		tok := advance_token(p)
 		stmt := parse_stmt(p)
-		switch s in stmt.derived {
-		case ast.Empty_Stmt:
+		#partial switch s in stmt.derived_stmt {
+		case ^ast.Empty_Stmt:
 			error(p, s.pos, "empty statement after defer (e.g. ';')")
-		case ast.Defer_Stmt:
+		case ^ast.Defer_Stmt:
 			error(p, s.pos, "you cannot defer a defer statement")
 			stmt = s.stmt
-		case ast.Return_Stmt:
+		case ^ast.Return_Stmt:
 			error(p, s.pos, "you cannot defer a return statement")
 		}
 		ds := ast.new(ast.Defer_Stmt, tok.pos, stmt.end)
@@ -1381,8 +1381,8 @@ parse_stmt :: proc(p: ^Parser) -> ^ast.Stmt {
 		expect_token_after(p, .Colon, "identifier list")
 		decl := parse_value_decl(p, list, docs)
 		if decl != nil {
-			switch d in &decl.derived {
-			case ast.Value_Decl:
+			#partial switch d in decl.derived_stmt {
+			case ^ast.Value_Decl:
 				d.is_using = true
 				return decl
 			}
@@ -1413,9 +1413,9 @@ parse_stmt :: proc(p: ^Parser) -> ^ast.Stmt {
 			return stmt
 		case "partial":
 			stmt := parse_stmt(p)
-			switch s in &stmt.derived {
-			case ast.Switch_Stmt:      s.partial = true
-			case ast.Type_Switch_Stmt: s.partial = true
+			#partial switch s in stmt.derived_stmt {
+			case ^ast.Switch_Stmt:      s.partial = true
+			case ^ast.Type_Switch_Stmt: s.partial = true
 			case: error(p, stmt.pos, "#partial can only be applied to a switch statement")
 			}
 			return stmt
@@ -1560,11 +1560,11 @@ parse_body :: proc(p: ^Parser) -> ^ast.Block_Stmt {
 }
 
 convert_stmt_to_body :: proc(p: ^Parser, stmt: ^ast.Stmt) -> ^ast.Stmt {
-	switch s in stmt.derived {
-	case ast.Block_Stmt:
+	#partial switch s in stmt.derived_stmt {
+	case ^ast.Block_Stmt:
 		error(p, stmt.pos, "expected a normal statement rather than a block statement")
 		return stmt
-	case ast.Empty_Stmt:
+	case ^ast.Empty_Stmt:
 		error(p, stmt.pos, "expected a non-empty statement")
 	}
 
@@ -1641,10 +1641,10 @@ convert_to_ident_list :: proc(p: ^Parser, list: []Expr_And_Flags, ignore_flags,
 
 		id: ^ast.Expr = ident.expr
 
-		switch n in ident.expr.derived {
-		case ast.Ident:
-		case ast.Bad_Expr:
-		case ast.Poly_Type:
+		#partial switch n in ident.expr.derived_expr {
+		case ^ast.Ident:
+		case ^ast.Bad_Expr:
+		case ^ast.Poly_Type:
 			if allow_poly_names {
 				if n.specialization == nil {
 					break
@@ -1806,21 +1806,21 @@ check_procedure_name_list :: proc(p: ^Parser, names: []^ast.Expr) -> bool {
 		return false
 	}
 
-	_, first_is_polymorphic := names[0].derived.(ast.Poly_Type)
+	_, first_is_polymorphic := names[0].derived.(^ast.Poly_Type)
 	any_polymorphic_names := first_is_polymorphic
 
 	for i := 1; i < len(names); i += 1 {
 		name := names[i]
 
 		if first_is_polymorphic {
-			if _, ok := name.derived.(ast.Poly_Type); ok {
+			if _, ok := name.derived.(^ast.Poly_Type); ok {
 				any_polymorphic_names = true
 			} else {
 				error(p, name.pos, "mixture of polymorphic and non-polymorphic identifiers")
 				return any_polymorphic_names
 			}
 		} else {
-			if _, ok := name.derived.(ast.Poly_Type); ok {
+			if _, ok := name.derived.(^ast.Poly_Type); ok {
 				any_polymorphic_names = true
 				error(p, name.pos, "mixture of polymorphic and non-polymorphic identifiers")
 				return any_polymorphic_names
@@ -1885,7 +1885,7 @@ parse_field_list :: proc(p: ^Parser, follow: tokenizer.Token_Kind, allowed_flags
 			if type == nil {
 				return false
 			}
-			_, ok := type.derived.(ast.Ellipsis)
+			_, ok := type.derived.(^ast.Ellipsis)
 			return ok
 		}
 
@@ -1903,7 +1903,7 @@ parse_field_list :: proc(p: ^Parser, follow: tokenizer.Token_Kind, allowed_flags
 			type = parse_var_type(p, allowed_flags)
 			tt := ast.unparen_expr(type)
 			if is_signature && !any_polymorphic_names {
-				if ti, ok := tt.derived.(ast.Typeid_Type); ok && ti.specialization != nil {
+				if ti, ok := tt.derived.(^ast.Typeid_Type); ok && ti.specialization != nil {
 					error(p, tt.pos, "specialization of typeid is not allowed without polymorphic names")
 				}
 			}
@@ -1979,7 +1979,7 @@ parse_field_list :: proc(p: ^Parser, follow: tokenizer.Token_Kind, allowed_flags
 	    p.curr_tok.kind != .EOF {
 		prefix_flags := parse_field_prefixes(p)
 		param := parse_var_type(p, allowed_flags & {.Typeid_Token, .Ellipsis})
-		if _, ok := param.derived.(ast.Ellipsis); ok {
+		if _, ok := param.derived.(^ast.Ellipsis); ok {
 			if seen_ellipsis {
 				error(p, param.pos, "extra variadic parameter after ellipsis")
 			}
@@ -2006,8 +2006,8 @@ parse_field_list :: proc(p: ^Parser, follow: tokenizer.Token_Kind, allowed_flags
 
 			names := make([]^ast.Expr, 1)
 			names[0] = ast.new(ast.Ident, tok.pos, end_pos(tok))
-			switch ident in &names[0].derived {
-			case ast.Ident:
+			#partial switch ident in names[0].derived_expr {
+			case ^ast.Ident:
 				ident.name = tok.text
 			case:
 				unreachable()
@@ -2137,12 +2137,12 @@ parse_proc_type :: proc(p: ^Parser, tok: tokenizer.Token) -> ^ast.Proc_Type {
 
 	loop: for param in params.list {
 		if param.type != nil {
-			if _, ok := param.type.derived.(ast.Poly_Type); ok {
+			if _, ok := param.type.derived.(^ast.Poly_Type); ok {
 				is_generic = true
 				break loop
 			}
 			for name in param.names {
-				if _, ok := name.derived.(ast.Poly_Type); ok {
+				if _, ok := name.derived.(^ast.Poly_Type); ok {
 					is_generic = true
 					break loop
 				}
@@ -2179,13 +2179,13 @@ parse_inlining_operand :: proc(p: ^Parser, lhs: bool, tok: tokenizer.Token) -> ^
 		}
 	}
 
-	switch e in &ast.unparen_expr(expr).derived {
-	case ast.Proc_Lit:
+	#partial switch e in ast.unparen_expr(expr).derived_expr {
+	case ^ast.Proc_Lit:
 		if e.inlining != .None && e.inlining != pi {
 			error(p, expr.pos, "both 'inline' and 'no_inline' cannot be applied to a procedure literal")
 		}
 		e.inlining = pi
-	case ast.Call_Expr:
+	case ^ast.Call_Expr:
 		if e.inlining != .None && e.inlining != pi {
 			error(p, expr.pos, "both 'inline' and 'no_inline' cannot be applied to a procedure call")
 		}
@@ -2276,9 +2276,9 @@ parse_operand :: proc(p: ^Parser, lhs: bool) -> ^ast.Expr {
 			bd.name = name.text
 			original_type := parse_type(p)
 			type := ast.unparen_expr(original_type)
-			switch t in &type.derived {
-			case ast.Array_Type:         t.tag = bd
-			case ast.Dynamic_Array_Type: t.tag = bd
+			#partial switch t in type.derived_expr {
+			case ^ast.Array_Type:         t.tag = bd
+			case ^ast.Dynamic_Array_Type: t.tag = bd
 			case:
 				error(p, original_type.pos, "expected an array type after #%s", name.text)
 			}
@@ -2290,10 +2290,10 @@ parse_operand :: proc(p: ^Parser, lhs: bool) -> ^ast.Expr {
 			tag.name = name.text
 			original_expr := parse_expr(p, lhs)
 			expr := ast.unparen_expr(original_expr)
-			switch t in &expr.derived {
-			case ast.Comp_Lit:
+			#partial switch t in expr.derived_expr {
+			case ^ast.Comp_Lit:
 				t.tag = tag
-			case ast.Array_Type:
+			case ^ast.Array_Type:
 				t.tag = tag
 				error(p, tok.pos, "#%s has been replaced with #sparse for non-contiguous enumerated array types", name.text)
 			case:
@@ -2308,8 +2308,8 @@ parse_operand :: proc(p: ^Parser, lhs: bool) -> ^ast.Expr {
 			tag.name = name.text
 			original_type := parse_type(p)
 			type := ast.unparen_expr(original_type)
-			switch t in &type.derived {
-			case ast.Array_Type:
+			#partial switch t in type.derived_expr {
+			case ^ast.Array_Type:
 				t.tag = tag
 			case:
 				error(p, tok.pos, "expected an enumerated array type after #%s", name.text)
@@ -2689,7 +2689,7 @@ parse_operand :: proc(p: ^Parser, lhs: bool) -> ^ast.Expr {
 		variants: [dynamic]^ast.Expr
 		for p.curr_tok.kind != .Close_Brace && p.curr_tok.kind != .EOF {
 			type := parse_type(p)
-			if _, ok := type.derived.(ast.Bad_Expr); !ok {
+			if _, ok := type.derived.(^ast.Bad_Expr); !ok {
 				append(&variants, type)
 			}
 			if !allow_token(p, .Comma) {
@@ -2864,19 +2864,19 @@ is_literal_type :: proc(expr: ^ast.Expr) -> bool {
 	if val == nil {
 		return false
 	}
-	switch _ in val.derived {
-	case ast.Bad_Expr,
-		ast.Ident,
-		ast.Selector_Expr,
-		ast.Array_Type,
-		ast.Struct_Type,
-		ast.Union_Type,
-		ast.Enum_Type,
-		ast.Dynamic_Array_Type,
-		ast.Map_Type,
-		ast.Bit_Set_Type,
-		ast.Matrix_Type,
-		ast.Call_Expr:
+	#partial switch _ in val.derived_expr {
+	case ^ast.Bad_Expr,
+		^ast.Ident,
+		^ast.Selector_Expr,
+		^ast.Array_Type,
+		^ast.Struct_Type,
+		^ast.Union_Type,
+		^ast.Enum_Type,
+		^ast.Dynamic_Array_Type,
+		^ast.Map_Type,
+		^ast.Bit_Set_Type,
+		^ast.Matrix_Type,
+		^ast.Call_Expr:
 		return true
 	}
 	return false
@@ -2998,7 +2998,7 @@ parse_call_expr :: proc(p: ^Parser, operand: ^ast.Expr) -> ^ast.Expr {
 	ce.close    = close.pos
 
 	o := ast.unparen_expr(operand)
-	if se, ok := o.derived.(ast.Selector_Expr); ok && se.op.kind == .Arrow_Right {
+	if se, ok := o.derived.(^ast.Selector_Expr); ok && se.op.kind == .Arrow_Right {
 		sce := ast.new(ast.Selector_Call_Expr, ce.pos, ce.end)
 		sce.expr = o
 		sce.call = ce
@@ -3428,13 +3428,13 @@ parse_simple_stmt :: proc(p: ^Parser, flags: Stmt_Allow_Flags) -> ^ast.Stmt {
 				stmt := parse_stmt(p)
 
 				if stmt != nil {
-					switch n in &stmt.derived {
-					case ast.Block_Stmt:       n.label = label
-					case ast.If_Stmt:          n.label = label
-					case ast.For_Stmt:         n.label = label
-					case ast.Switch_Stmt:      n.label = label
-					case ast.Type_Switch_Stmt: n.label = label
-					case ast.Range_Stmt:	   n.label = label
+					#partial switch n in stmt.derived_stmt {
+					case ^ast.Block_Stmt:       n.label = label
+					case ^ast.If_Stmt:          n.label = label
+					case ^ast.For_Stmt:         n.label = label
+					case ^ast.Switch_Stmt:      n.label = label
+					case ^ast.Type_Switch_Stmt: n.label = label
+					case ^ast.Range_Stmt:	    n.label = label
 					}
 				}
 
diff --git a/core/odin/printer/visit.odin b/core/odin/printer/visit.odin
index 023583bde..9eba29987 100644
--- a/core/odin/printer/visit.odin
+++ b/core/odin/printer/visit.odin
@@ -342,16 +342,16 @@ visit_decl :: proc(p: ^Printer, decl: ^ast.Decl, called_in_stmt := false) {
 		return

 	}

 

-	switch v in &decl.derived {

-	case Expr_Stmt:

+	#partial switch v in decl.derived_stmt {

+	case ^Expr_Stmt:

 		move_line(p, decl.pos)

 		visit_expr(p, v.expr)

 		if p.config.semicolons {

 			push_generic_token(p, .Semicolon, 0)

 		}

-	case When_Stmt:

+	case ^When_Stmt:

 		visit_stmt(p, cast(^Stmt)decl)

-	case Foreign_Import_Decl:

+	case ^Foreign_Import_Decl:

 		if len(v.attributes) > 0 {

 			sort.sort(sort_attribute(&v.attributes))

 			move_line(p, v.attributes[0].pos)

@@ -370,7 +370,7 @@ visit_decl :: proc(p: ^Printer, decl: ^ast.Decl, called_in_stmt := false) {
 		for path in v.fullpaths {

 			push_ident_token(p, path, 0)

 		}

-	case Foreign_Block_Decl:

+	case ^Foreign_Block_Decl:

 		if len(v.attributes) > 0 {

 			sort.sort(sort_attribute(&v.attributes))

 			move_line(p, v.attributes[0].pos)

@@ -383,7 +383,7 @@ visit_decl :: proc(p: ^Printer, decl: ^ast.Decl, called_in_stmt := false) {
 

 		visit_expr(p, v.foreign_library)

 		visit_stmt(p, v.body)

-	case Import_Decl:

+	case ^Import_Decl:

 		move_line(p, decl.pos)

 

 		if v.name.text != "" {

@@ -395,7 +395,7 @@ visit_decl :: proc(p: ^Printer, decl: ^ast.Decl, called_in_stmt := false) {
 			push_ident_token(p, v.fullpath, 1)

 		}

 

-	case Value_Decl:

+	case ^Value_Decl:

 		if len(v.attributes) > 0 {

 			sort.sort(sort_attribute(&v.attributes))

 			move_line(p, v.attributes[0].pos)

@@ -446,10 +446,10 @@ visit_decl :: proc(p: ^Printer, decl: ^ast.Decl, called_in_stmt := false) {
 		add_semicolon := true

 

 		for value in v.values {

-			switch a in value.derived {

-			case Union_Type, Enum_Type, Struct_Type:

+			#partial switch a in value.derived {

+			case ^Union_Type, ^Enum_Type, ^Struct_Type:

 				add_semicolon = false || called_in_stmt

-			case Proc_Lit:

+			case ^Proc_Lit:

 				add_semicolon = false

 			}

 		}

@@ -516,23 +516,34 @@ visit_stmt :: proc(p: ^Printer, stmt: ^ast.Stmt, block_type: Block_Type = .Gener
 		return

 	}

 

-	switch v in stmt.derived {

-	case Import_Decl:

+

+	switch v in stmt.derived_stmt {

+	case ^Bad_Stmt:

+	case ^Bad_Decl:

+	case ^Package_Decl:

+

+	case ^Empty_Stmt:

+		push_generic_token(p, .Semicolon, 0)

+	case ^Tag_Stmt:

+		push_generic_token(p, .Hash, 1)

+		push_generic_token(p, v.op.kind, 1, v.op.text)

+		visit_stmt(p, v.stmt)

+

+

+	case ^Import_Decl:

 		visit_decl(p, cast(^Decl)stmt, true)

 		return

-	case Value_Decl:

+	case ^Value_Decl:

 		visit_decl(p, cast(^Decl)stmt, true)

 		return

-	case Foreign_Import_Decl:

+	case ^Foreign_Import_Decl:

 		visit_decl(p, cast(^Decl)stmt, true)

 		return

-	case Foreign_Block_Decl:

+	case ^Foreign_Block_Decl:

 		visit_decl(p, cast(^Decl)stmt, true)

 		return

-	}

 

-	switch v in stmt.derived {

-	case Using_Stmt:

+	case ^Using_Stmt:

 		move_line(p, v.pos)

 

 		push_generic_token(p, .Using, 1)

@@ -542,7 +553,7 @@ visit_stmt :: proc(p: ^Printer, stmt: ^ast.Stmt, block_type: Block_Type = .Gener
 		if p.config.semicolons {

 			push_generic_token(p, .Semicolon, 0)

 		}

-	case Block_Stmt:

+	case ^Block_Stmt:

 		move_line(p, v.pos)

 

 		if v.pos.line == v.end.line {

@@ -572,7 +583,7 @@ visit_stmt :: proc(p: ^Printer, stmt: ^ast.Stmt, block_type: Block_Type = .Gener
 				visit_end_brace(p, v.end)

 			}

 		}

-	case If_Stmt:

+	case ^If_Stmt:

 		move_line(p, v.pos)

 

 		if v.label != nil {

@@ -595,7 +606,7 @@ visit_stmt :: proc(p: ^Printer, stmt: ^ast.Stmt, block_type: Block_Type = .Gener
 

 		uses_do := false

 

-		if check_stmt, ok := v.body.derived.(Block_Stmt); ok && check_stmt.uses_do {

+		if check_stmt, ok := v.body.derived.(^Block_Stmt); ok && check_stmt.uses_do {

 			uses_do = true

 		}

 

@@ -626,7 +637,7 @@ visit_stmt :: proc(p: ^Printer, stmt: ^ast.Stmt, block_type: Block_Type = .Gener
 

 			visit_stmt(p, v.else_stmt)

 		}

-	case Switch_Stmt:

+	case ^Switch_Stmt:

 		move_line(p, v.pos)

 

 		if v.label != nil {

@@ -654,7 +665,7 @@ visit_stmt :: proc(p: ^Printer, stmt: ^ast.Stmt, block_type: Block_Type = .Gener
 

 		visit_expr(p, v.cond)

 		visit_stmt(p, v.body)

-	case Case_Clause:

+	case ^Case_Clause:

 		move_line(p, v.pos)

 

 		if !p.config.indent_cases {

@@ -678,7 +689,7 @@ visit_stmt :: proc(p: ^Printer, stmt: ^ast.Stmt, block_type: Block_Type = .Gener
 		if !p.config.indent_cases {

 			indent(p)

 		}

-	case Type_Switch_Stmt:

+	case ^Type_Switch_Stmt:

 		move_line(p, v.pos)

 

 		hint_current_line(p, {.Switch_Stmt})

@@ -696,7 +707,7 @@ visit_stmt :: proc(p: ^Printer, stmt: ^ast.Stmt, block_type: Block_Type = .Gener
 

 		visit_stmt(p, v.tag)

 		visit_stmt(p, v.body)

-	case Assign_Stmt:

+	case ^Assign_Stmt:

 		move_line(p, v.pos)

 

 		hint_current_line(p, {.Assign})

@@ -710,13 +721,13 @@ visit_stmt :: proc(p: ^Printer, stmt: ^ast.Stmt, block_type: Block_Type = .Gener
 		if block_stmt && p.config.semicolons {

 			push_generic_token(p, .Semicolon, 0)

 		}

-	case Expr_Stmt:

+	case ^Expr_Stmt:

 		move_line(p, v.pos)

 		visit_expr(p, v.expr)

 		if block_stmt && p.config.semicolons {

 			push_generic_token(p, .Semicolon, 0)

 		}

-	case For_Stmt:

+	case ^For_Stmt:

 		// this should be simplified

 		move_line(p, v.pos)

 

@@ -753,7 +764,7 @@ visit_stmt :: proc(p: ^Printer, stmt: ^ast.Stmt, block_type: Block_Type = .Gener
 

 		visit_stmt(p, v.body)

 

-	case Inline_Range_Stmt:

+	case ^Inline_Range_Stmt:

 		move_line(p, v.pos)

 

 		if v.label != nil {

@@ -779,7 +790,7 @@ visit_stmt :: proc(p: ^Printer, stmt: ^ast.Stmt, block_type: Block_Type = .Gener
 		visit_expr(p, v.expr)

 		visit_stmt(p, v.body)

 

-	case Range_Stmt:

+	case ^Range_Stmt:

 		move_line(p, v.pos)

 

 		if v.label != nil {

@@ -805,7 +816,7 @@ visit_stmt :: proc(p: ^Printer, stmt: ^ast.Stmt, block_type: Block_Type = .Gener
 		visit_expr(p, v.expr)

 

 		visit_stmt(p, v.body)

-	case Return_Stmt:

+	case ^Return_Stmt:

 		move_line(p, v.pos)

 

 		push_generic_token(p, .Return, 1)

@@ -817,7 +828,7 @@ visit_stmt :: proc(p: ^Printer, stmt: ^ast.Stmt, block_type: Block_Type = .Gener
 		if block_stmt && p.config.semicolons {

 			push_generic_token(p, .Semicolon, 0)

 		}

-	case Defer_Stmt:

+	case ^Defer_Stmt:

 		move_line(p, v.pos)

 		push_generic_token(p, .Defer, 0)

 

@@ -826,7 +837,7 @@ visit_stmt :: proc(p: ^Printer, stmt: ^ast.Stmt, block_type: Block_Type = .Gener
 		if p.config.semicolons {

 			push_generic_token(p, .Semicolon, 0)

 		}

-	case When_Stmt:

+	case ^When_Stmt:

 		move_line(p, v.pos)

 		push_generic_token(p, .When, 1)

 		visit_expr(p, v.cond)

@@ -846,7 +857,7 @@ visit_stmt :: proc(p: ^Printer, stmt: ^ast.Stmt, block_type: Block_Type = .Gener
 			visit_stmt(p, v.else_stmt)

 		}

 

-	case Branch_Stmt:

+	case ^Branch_Stmt:

 		move_line(p, v.pos)

 

 		push_generic_token(p, v.tok.kind, 0)

@@ -918,8 +929,15 @@ visit_expr :: proc(p: ^Printer, expr: ^ast.Expr, options := List_Options{}) {
 

 	set_source_position(p, expr.pos)

 

-	switch v in expr.derived {

-	case Inline_Asm_Expr:

+	switch v in expr.derived_expr {

+	case ^Bad_Expr:

+

+	case ^Tag_Expr:

+		push_generic_token(p, .Hash, 1)

+		push_generic_token(p, v.op.kind, 1, v.op.text)

+		visit_expr(p, v.expr)

+

+	case ^Inline_Asm_Expr:

 		push_generic_token(p, v.tok.kind, 1, v.tok.text)

 

 		push_generic_token(p, .Open_Paren, 1)

@@ -936,42 +954,42 @@ visit_expr :: proc(p: ^Printer, expr: ^ast.Expr, options := List_Options{}) {
 		push_generic_token(p, .Comma, 0)

 		visit_expr(p, v.constraints_string)

 		push_generic_token(p, .Close_Brace, 0)

-	case Undef:

+	case ^Undef:

 		push_generic_token(p, .Undef, 1)

-	case Auto_Cast:

+	case ^Auto_Cast:

 		push_generic_token(p, v.op.kind, 1)

 		visit_expr(p, v.expr)

-	case Ternary_If_Expr:

+	case ^Ternary_If_Expr:

 		visit_expr(p, v.x)

 		push_generic_token(p, v.op1.kind, 1)

 		visit_expr(p, v.cond)

 		push_generic_token(p, v.op2.kind, 1)

 		visit_expr(p, v.y)

-	case Ternary_When_Expr:

+	case ^Ternary_When_Expr:

 		visit_expr(p, v.x)

 		push_generic_token(p, v.op1.kind, 1)

 		visit_expr(p, v.cond)

 		push_generic_token(p, v.op2.kind, 1)

 		visit_expr(p, v.y)

-	case Or_Else_Expr:

+	case ^Or_Else_Expr:

 		visit_expr(p, v.x)

 		push_generic_token(p, v.token.kind, 1)

 		visit_expr(p, v.y)

-	case Or_Return_Expr:

+	case ^Or_Return_Expr:

 		visit_expr(p, v.expr)

 		push_generic_token(p, v.token.kind, 1)

-	case Selector_Call_Expr:

+	case ^Selector_Call_Expr:

 		visit_expr(p, v.call.expr)

 		push_generic_token(p, .Open_Paren, 1)

 		visit_exprs(p, v.call.args, {.Add_Comma})

 		push_generic_token(p, .Close_Paren, 0)

-	case Ellipsis:

+	case ^Ellipsis:

 		push_generic_token(p, .Ellipsis, 1)

 		visit_expr(p, v.expr)

-	case Relative_Type:

+	case ^Relative_Type:

 		visit_expr(p, v.tag)

 		visit_expr(p, v.type)

-	case Slice_Expr:

+	case ^Slice_Expr:

 		visit_expr(p, v.expr)

 		push_generic_token(p, .Open_Bracket, 0)

 		visit_expr(p, v.low)

@@ -981,37 +999,37 @@ visit_expr :: proc(p: ^Printer, expr: ^ast.Expr, options := List_Options{}) {
 			visit_expr(p, v.high)

 		}

 		push_generic_token(p, .Close_Bracket, 0)

-	case Ident:

+	case ^Ident:

 		if .Enforce_Poly_Names in options {

 			push_generic_token(p, .Dollar, 1)

 			push_ident_token(p, v.name, 0)

 		} else {

 			push_ident_token(p, v.name, 1)

 		}

-	case Deref_Expr:

+	case ^Deref_Expr:

 		visit_expr(p, v.expr)

 		push_generic_token(p, v.op.kind, 0)

-	case Type_Cast:

+	case ^Type_Cast:

 		push_generic_token(p, v.tok.kind, 1)

 		push_generic_token(p, .Open_Paren, 0)

 		visit_expr(p, v.type)

 		push_generic_token(p, .Close_Paren, 0)

 		merge_next_token(p)

 		visit_expr(p, v.expr)

-	case Basic_Directive:

+	case ^Basic_Directive:

 		push_generic_token(p, v.tok.kind, 1)

 		push_ident_token(p, v.name, 0)

-	case Distinct_Type:

+	case ^Distinct_Type:

 		push_generic_token(p, .Distinct, 1)

 		visit_expr(p, v.type)

-	case Dynamic_Array_Type:

+	case ^Dynamic_Array_Type:

 		visit_expr(p, v.tag)

 		push_generic_token(p, .Open_Bracket, 1)

 		push_generic_token(p, .Dynamic, 0)

 		push_generic_token(p, .Close_Bracket, 0)

 		merge_next_token(p)

 		visit_expr(p, v.elem)

-	case Bit_Set_Type:

+	case ^Bit_Set_Type:

 		push_generic_token(p, .Bit_Set, 1)

 		push_generic_token(p, .Open_Bracket, 0)

 

@@ -1023,7 +1041,7 @@ visit_expr :: proc(p: ^Printer, expr: ^ast.Expr, options := List_Options{}) {
 		}

 

 		push_generic_token(p, .Close_Bracket, 0)

-	case Union_Type:

+	case ^Union_Type:

 		push_generic_token(p, .Union, 1)

 

 		push_poly_params(p, v.poly_params)

@@ -1045,7 +1063,7 @@ visit_expr :: proc(p: ^Printer, expr: ^ast.Expr, options := List_Options{}) {
 			visit_exprs(p, v.variants, {.Add_Comma, .Trailing})

 			visit_end_brace(p, v.end)

 		}

-	case Enum_Type:

+	case ^Enum_Type:

 		push_generic_token(p, .Enum, 1)

 

 		hint_current_line(p, {.Enum})

@@ -1068,7 +1086,7 @@ visit_expr :: proc(p: ^Printer, expr: ^ast.Expr, options := List_Options{}) {
 		}

 

 		set_source_position(p, v.end)

-	case Struct_Type:

+	case ^Struct_Type:

 		push_generic_token(p, .Struct, 1)

 

 		hint_current_line(p, {.Struct})

@@ -1103,7 +1121,7 @@ visit_expr :: proc(p: ^Printer, expr: ^ast.Expr, options := List_Options{}) {
 		}

 

 		set_source_position(p, v.end)

-	case Proc_Lit:

+	case ^Proc_Lit:

 		switch v.inlining {

 		case .None:

 		case .Inline:

@@ -1112,7 +1130,7 @@ visit_expr :: proc(p: ^Printer, expr: ^ast.Expr, options := List_Options{}) {
 			push_ident_token(p, "#force_no_inline", 0)

 		}

 

-		visit_proc_type(p, v.type^, true)

+		visit_proc_type(p, v.type, true)

 

 		push_where_clauses(p, v.where_clauses)

 

@@ -1122,16 +1140,16 @@ visit_expr :: proc(p: ^Printer, expr: ^ast.Expr, options := List_Options{}) {
 		} else {

 			push_generic_token(p, .Undef, 1)

 		}

-	case Proc_Type:

+	case ^Proc_Type:

 		visit_proc_type(p, v)

-	case Basic_Lit:

+	case ^Basic_Lit:

 		push_generic_token(p, v.tok.kind, 1, v.tok.text)

-	case Binary_Expr:

+	case ^Binary_Expr:

 		visit_binary_expr(p, v)

-	case Implicit_Selector_Expr:

+	case ^Implicit_Selector_Expr:

 		push_generic_token(p, .Period, 1)

 		push_ident_token(p, v.field.name, 0)

-	case Call_Expr:

+	case ^Call_Expr:

 		visit_expr(p, v.expr)

 

 		push_format_token(p,

@@ -1146,27 +1164,34 @@ visit_expr :: proc(p: ^Printer, expr: ^ast.Expr, options := List_Options{}) {
 

 		visit_call_exprs(p, v.args, v.ellipsis.kind == .Ellipsis)

 		push_generic_token(p, .Close_Paren, 0)

-	case Typeid_Type:

+	case ^Typeid_Type:

 		push_generic_token(p, .Typeid, 1)

 

 		if v.specialization != nil {

 			push_generic_token(p, .Quo, 0)

 			visit_expr(p, v.specialization)

 		}

-	case Selector_Expr:

+	case ^Selector_Expr:

 		visit_expr(p, v.expr)

 		push_generic_token(p, v.op.kind, 0)

 		visit_expr(p, v.field)

-	case Paren_Expr:

+	case ^Paren_Expr:

 		push_generic_token(p, .Open_Paren, 1)

 		visit_expr(p, v.expr)

 		push_generic_token(p, .Close_Paren, 0)

-	case Index_Expr:

+	case ^Index_Expr:

 		visit_expr(p, v.expr)

 		push_generic_token(p, .Open_Bracket, 0)

 		visit_expr(p, v.index)

 		push_generic_token(p, .Close_Bracket, 0)

-	case Proc_Group:

+	case ^Matrix_Index_Expr:

+		visit_expr(p, v.expr)

+		push_generic_token(p, .Open_Bracket, 0)

+		visit_expr(p, v.row_index)

+		push_generic_token(p, .Comma, 0)

+		visit_expr(p, v.column_index)

+		push_generic_token(p, .Close_Bracket, 0)

+	case ^Proc_Group:

 		push_generic_token(p, v.tok.kind, 1)

 

 		if len(v.args) != 0 && v.pos.line != v.args[len(v.args) - 1].pos.line {

@@ -1181,7 +1206,7 @@ visit_expr :: proc(p: ^Printer, expr: ^ast.Expr, options := List_Options{}) {
 			push_generic_token(p, .Close_Brace, 0)

 		}

 

-	case Comp_Lit:

+	case ^Comp_Lit:

 		if v.type != nil {

 			visit_expr(p, v.type)

 		}

@@ -1198,18 +1223,18 @@ visit_expr :: proc(p: ^Printer, expr: ^ast.Expr, options := List_Options{}) {
 			push_generic_token(p, .Close_Brace, 0)

 		}

 

-	case Unary_Expr:

+	case ^Unary_Expr:

 		push_generic_token(p, v.op.kind, 1)

 		merge_next_token(p)

 		visit_expr(p, v.expr)

-	case Field_Value:

+	case ^Field_Value:

 		visit_expr(p, v.field)

 		push_generic_token(p, .Eq, 1)

 		visit_expr(p, v.value)

-	case Type_Assertion:

+	case ^Type_Assertion:

 		visit_expr(p, v.expr)

 

-		if unary, ok := v.type.derived.(Unary_Expr); ok && unary.op.text == "?" {

+		if unary, ok := v.type.derived.(^Unary_Expr); ok && unary.op.text == "?" {

 			push_generic_token(p, .Period, 0)

 			visit_expr(p, v.type)

 		} else {

@@ -1219,13 +1244,13 @@ visit_expr :: proc(p: ^Printer, expr: ^ast.Expr, options := List_Options{}) {
 			push_generic_token(p, .Close_Paren, 0)

 		}

 

-	case Pointer_Type:

+	case ^Pointer_Type:

 		push_generic_token(p, .Pointer, 1)

 		merge_next_token(p)

 		visit_expr(p, v.elem)

-	case Implicit:

+	case ^Implicit:

 		push_generic_token(p, v.tok.kind, 1)

-	case Poly_Type:

+	case ^Poly_Type:

 		push_generic_token(p, .Dollar, 1)

 		merge_next_token(p)

 		visit_expr(p, v.type)

@@ -1235,22 +1260,35 @@ visit_expr :: proc(p: ^Printer, expr: ^ast.Expr, options := List_Options{}) {
 			merge_next_token(p)

 			visit_expr(p, v.specialization)

 		}

-	case Array_Type:

+	case ^Array_Type:

 		visit_expr(p, v.tag)

 		push_generic_token(p, .Open_Bracket, 1)

 		visit_expr(p, v.len)

 		push_generic_token(p, .Close_Bracket, 0)

 		merge_next_token(p)

 		visit_expr(p, v.elem)

-	case Map_Type:

+	case ^Map_Type:

 		push_generic_token(p, .Map, 1)

 		push_generic_token(p, .Open_Bracket, 0)

 		visit_expr(p, v.key)

 		push_generic_token(p, .Close_Bracket, 0)

 		merge_next_token(p)

 		visit_expr(p, v.value)

-	case Helper_Type:

+	case ^Helper_Type:

 		visit_expr(p, v.type)

+	case ^Multi_Pointer_Type:

+		push_generic_token(p, .Open_Bracket, 1)

+		push_generic_token(p, .Pointer, 0)

+		push_generic_token(p, .Close_Bracket, 0)

+		visit_expr(p, v.elem)

+	case ^Matrix_Type:

+		push_generic_token(p, .Matrix, 1)

+		push_generic_token(p, .Open_Bracket, 0)

+		visit_expr(p, v.row_count)

+		push_generic_token(p, .Comma, 0)

+		visit_expr(p, v.column_count)

+		push_generic_token(p, .Close_Bracket, 0)

+		visit_expr(p, v.elem)

 	case:

 		panic(fmt.aprint(expr.derived))

 	}

@@ -1348,7 +1386,7 @@ visit_field_list :: proc(p: ^Printer, list: ^ast.Field_List, options := List_Opt
 	}

 }

 

-visit_proc_type :: proc(p: ^Printer, proc_type: ast.Proc_Type, is_proc_lit := false) {

+visit_proc_type :: proc(p: ^Printer, proc_type: ^ast.Proc_Type, is_proc_lit := false) {

 	if is_proc_lit {

 		push_format_token(p, Format_Token {

 			kind = .Proc,

@@ -1392,7 +1430,7 @@ visit_proc_type :: proc(p: ^Printer, proc_type: ast.Proc_Type, is_proc_lit := fa
 		} else if len(proc_type.results.list) == 1 {

 

 			for name in proc_type.results.list[0].names {

-				if ident, ok := name.derived.(ast.Ident); ok {

+				if ident, ok := name.derived.(^ast.Ident); ok {

 					if ident.name != "_" {

 						use_parens = true

 					}

@@ -1410,19 +1448,19 @@ visit_proc_type :: proc(p: ^Printer, proc_type: ast.Proc_Type, is_proc_lit := fa
 	}

 }

 

-visit_binary_expr :: proc(p: ^Printer, binary: ast.Binary_Expr) {

+visit_binary_expr :: proc(p: ^Printer, binary: ^ast.Binary_Expr) {

 	move_line(p, binary.left.pos)

 

-	if v, ok := binary.left.derived.(ast.Binary_Expr); ok {

+	if v, ok := binary.left.derived.(^ast.Binary_Expr); ok {

 		visit_binary_expr(p, v)

 	} else {

 		visit_expr(p, binary.left)

 	}

 

 	either_implicit_selector := false

-	if _, ok := binary.left.derived.(ast.Implicit_Selector_Expr); ok {

+	if _, ok := binary.left.derived.(^ast.Implicit_Selector_Expr); ok {

 		either_implicit_selector = true

-	} else if _, ok := binary.right.derived.(ast.Implicit_Selector_Expr); ok {

+	} else if _, ok := binary.right.derived.(^ast.Implicit_Selector_Expr); ok {

 		either_implicit_selector = true

 	}

 

@@ -1439,7 +1477,7 @@ visit_binary_expr :: proc(p: ^Printer, binary: ast.Binary_Expr) {
 	move_line(p, binary.right.pos)

 

 

-	if v, ok := binary.right.derived.(ast.Binary_Expr); ok {

+	if v, ok := binary.right.derived.(^ast.Binary_Expr); ok {

 		visit_binary_expr(p, v)

 	} else {

 		visit_expr(p, binary.right)

@@ -1499,7 +1537,7 @@ visit_signature_list :: proc(p: ^Printer, list: ^ast.Field_List, remove_blank :=
 		named := false

 

 		for name in field.names {

-			if ident, ok := name.derived.(ast.Ident); ok {

+			if ident, ok := name.derived.(^ast.Ident); ok {

 				//for some reason the parser uses _ to mean empty

 				if ident.name != "_" || !remove_blank {

 					named = true

diff --git a/core/reflect/reflect.odin b/core/reflect/reflect.odin
index 05b3a5da0..d05026532 100644
--- a/core/reflect/reflect.odin
+++ b/core/reflect/reflect.odin
@@ -365,6 +365,19 @@ index :: proc(val: any, i: int, loc := #caller_location) -> any {
 	return nil
 }
 
+deref :: proc(val: any) -> any {
+	if val != nil {
+		ti := type_info_base(type_info_of(val.id))
+		if info, ok := ti.variant.(Type_Info_Pointer); ok {
+			return any{
+				(^rawptr)(val.data)^,
+				info.elem.id,
+			}
+		}
+	}
+	return val
+}
+
 
 
 // Struct_Tag represents the type of the string of a struct field
@@ -680,7 +693,6 @@ union_variant_typeid :: proc(a: any) -> typeid {
 		return nil
 	}
 	panic("expected a union to reflect.union_variant_typeid")
-
 }
 
 get_union_variant_raw_tag :: proc(a: any) -> i64 {