JavaScript使用属性创建非对象变量

Question

我想要一个具有＆＃34; main＆＃34;的变量。值但具有只能与该变量一起使用的新属性

<script type="text/javascript">
    var myVar="random value";
    myVar.prop1="other value"; //How do I make it so that myVar can have that property, but other strings can't
</script>