Add contracts on @catch / @ok. Taking the $typeof of a wildcard optional returns void!

lib/std/core/builtin.c3

@@ -324,13 +324,24 @@ macro swizzle2(v, v2, ...) @builtin
 {
 	return $$swizzle2(v, v2, $vasplat);
 }
+<*
+ Return the excuse in the Optional if it is Empty, otherwise
+ return a null fault.
 
+ @require @typekind(#expr) == OPTIONAL : `@catch expects an Optional value`
+*>
 macro anyfault @catch(#expr) @builtin
 {
 	if (catch f = #expr) return f;
 	return anyfault {};
 }
 
+<*
+ Check if an Optional expression holds a value or is empty, returning true
+ if it has a value.
+
+ @require @typekind(#expr) == OPTIONAL : `@ok expects an Optional value`
+*>
 macro bool @ok(#expr) @builtin
 {
 	if (catch #expr) return false;

releasenotes.md

@@ -57,6 +57,7 @@
 - Fixes with error handling recursive `@tag` #1583.
 - Sometimes generating introspection info would not be in the global scope causing a crash #1586.
 - @tag on macros cannot be retrieved with tagof #1582
+- Taking the $typeof of a wildcard optional returns `void!`.
 
 ### Stdlib changes
 - Remove unintended print of `char[]` as String

src/compiler/sema_types.c

@@ -325,6 +325,11 @@ INLINE bool sema_resolve_typeof(SemaContext *context, TypeInfo *type_info)
 			type_info->type = expr_type;
 			return true;
 		case STORAGE_WILDCARD:
+			if (expr_type->type_kind == TYPE_OPTIONAL)
+			{
+				type_info->type = type_get_optional(type_void);
+				return true;
+			}
 			RETURN_SEMA_ERROR(expr, "This %sexpression lacks a concrete type.", type_is_optional(expr_type) ? "optional " : "");
 		case STORAGE_COMPILE_TIME:
 			RETURN_SEMA_ERROR(expr, "This expression has a compile time type %s.", type_quoted_error_string(expr_type));

test/test_suite/cast/cast_to_failable.c3

@@ -7,7 +7,7 @@ fn void test()
 {
     int! x;
     double! y;
-    int! d = ($typeof(MyErr.FOO?))(x); // #error: optional expression lacks a concrete
+    int! d = ($typeof(MyErr.FOO?))(x); // #error: Casting to an optional
     int! df = ($typeof(y))(x); // #error: Casting to an optional type is not allowed
     double! df2 = ($typeof(y!!))(x);
 }

test/test_suite/errors/optional_sizeof.c3

@@ -3,33 +3,38 @@ fn int! abc()
 	return 1;
 }
 macro test()
+{
+	return @catch(abc())?!!;
+}
+
+macro test2()
 {
 	return @catch(abc())?;
 }
 
 fn void a()
 {
-	String s = $typeof(test()).qnameof; // #error: This optional expression lacks
+	String s = $typeof(test()).qnameof; // #error: This expression lacks
 }
 
 fn void b()
 {
-	$sizeof(test()); // #error: This optional expression lacks
+	$sizeof(test()); // #error: This expression lacks
 }
 
 fn void c()
 {
-	$sizeof(test() ?? 1);
+	$sizeof(test2() ?? 1);
 }
 
 fn void! d()
 {
-	$typeof(test()!) g; // #error: This expression lacks a concrete type
+	$typeof(test2()!) g; // #error: This expression lacks a concrete type
 }
 
 macro e()
 {
-	var g = test()!; // #error: No type can be inferred from the optional result
+	var g = test2()!; // #error: No type can be inferred from the optional result
 }
 
 fn void! h()