ast, parser: fix reference typenode (#15346)

vlib/v/ast/ast.v

@@ -112,8 +112,9 @@ pub type Node = CallArg
 
 pub struct TypeNode {
 pub:
-	typ Type
 	pos token.Pos
+pub mut:
+	typ Type
 }
 
 pub enum ComptimeTypeKind {

vlib/v/parser/expr.v

@@ -607,6 +607,10 @@ fn (mut p Parser) prefix_expr() ast.Expr {
 				right = right.expr
 			}
 		}
+		if mut right is ast.TypeNode {
+			right.typ = right.typ.ref()
+			return right
+		}
 	}
 	mut or_stmts := []ast.Stmt{}
 	mut or_kind := ast.OrKind.absent

vlib/v/tests/inout/printing_comptime_if.out

@@ -0,0 +1 @@
+T is &u8

vlib/v/tests/inout/printing_comptime_if.vv

@@ -0,0 +1,10 @@
+fn main() {
+	c := c'cstr'
+	proc(c)
+}
+
+fn proc<T>(input T) {
+	$if T is &u8 {
+		println('T is $T.name')
+	}
+}