Stand-In Types

What They Are

Stand-in types are Cleet's mechanism to allow collections to be used to store any class, with full compile-time type checking. They serve the same purpose that C++'s templates usually do. They are also by far the most broken feature of the current compiler, which barely handles them well enough to make the List class work.

Using Stand-In Types

To see how stand-in types are declared and used, let's look at an excerpt from the source for List:

Class: List
Stand-In-Types: Type

append(object: Type)
{
  // ...
}

first-item: Type
{
  // ...
}

Type is the stand-in type, and can represent any class. Which class it represents is determined when a variable of type List is declared:

names: List of String;

names.append("Hello");
some-name: String = names.first-item;

Using the wrong type will raise an error at compile time. For example, this is illegal:

names.append(new MyClass);

What happens if you don't give the type? In that case it defaults to Object. So the following two declarations are equivalent:

list: List;
list: List of Object;