The type(expr, appliable) calling sequence returns true if expr, when applied to some expression or expression sequence, may evaluate to an expression that is not of type .

More specifically, expr is appliable if one of the following is true:

- It is one of the following types.

- It is of type @ and all its operands are appliable.

- It is of type @@ and its first operand is appliable.

- It is of type indexed and its zeroth operand is appliable.

- It is an appliable module.

- It is of type function, and an evalapply rule exists for its zeroth operand.

type( proc() end proc, appliable );