Represent a declaration of a type representing expressions of the form foo[_Integer,_Real] but that internally stores the data in a product type:

Compile a function which instantiates and returns an object with the new type:

Represent a declaration of a type representing expressions with the head foo and length 2 and that internally stores the data in an expression:

Compile a function that takes foo as an argument and returns it unchanged:

The function accepts expressions that have the specified structure:

But rejects expressions that do not have the specified structure:

A declaration of a type representing expressions with head foo and that takes any number in its first argument and a Boolean in its second argument:

Compile a function that returns an object with that type:

Note that the return type of the function is parameterized by the type of number that the foo takes in its first argument.

A declaration of a type representing expressions with head foo and that takes any two arguments:

Compile a function that returns an object with that type:

Note that the return type of the function is parameterized by the two argument types. This is equivalent to declaring a compiled expression that has unrestricted type variables in both arguments: