fix

ark/schema/structure/optional.ts

@@ -103,13 +103,13 @@ export const assertDefaultValueAssignability = (
 	value: unknown,
 	key = ""
 ): unknown => {
-	if (!isPrimitive(value) && typeof value !== "function") {
-		throwParseError(writeNonPrimitiveNonFunctionDefaultValueMessage(key, value))
-	}
+	if (!isPrimitive(value) && typeof value !== "function")
+		throwParseError(writeNonPrimitiveNonFunctionDefaultValueMessage(key))
+
 	const out = node.in(typeof value === "function" ? value() : value)
-	if (out instanceof ArkErrors) {
+	if (out instanceof ArkErrors)
 		throwParseError(writeUnassignableDefaultValueMessage(out.message, key))
-	}
+
 	return value
 }
 
@@ -124,7 +124,6 @@ export type writeUnassignableDefaultValueMessage<
 > = `Default value ${defaultValue} is not assignable to ${baseDef}`
 
 export const writeNonPrimitiveNonFunctionDefaultValueMessage = (
-	key: string,
-	value: unknown
+	key: string
 ): string =>
-	`Default value${key && ` for key ${key}`} is not primitive so it should be constructor function (was ${printable(value)})`
+	`Default value${key && ` for key ${key}`} is not primitive so it should be specified as a function like () => ({my: 'object'})`

ark/type/__tests__/defaults.test.ts

@@ -228,7 +228,7 @@ contextualize(() => {
 			const time = v1.date.getTime()
 			v1.date.setMilliseconds(123)
 			const v2 = t.assert({})
-			attest(v1.date.getTime()).equals(time)
+			attest(v2.date.getTime()).equals(time)
 		})
 
 		it("true", () => {

ark/type/parser/shift/operator/default.ts

@@ -27,8 +27,11 @@ export const parseDefault = (s: DynamicStateWithRoot): BaseRoot => {
 	// token from which it was parsed
 	if (!defaultNode.hasKind("unit"))
 		return s.error(writeNonLiteralDefaultMessage(defaultNode.expression))
-
-	return baseNode.default(defaultNode.unit)
+	const defaultValue =
+		defaultNode.unit instanceof Date ?
+			() => new Date(defaultNode.unit as Date)
+		:	defaultNode.unit
+	return baseNode.default(defaultValue)
 }
 
 export type parseDefault<root, unscanned extends string> =