You can control type specialization to a certain extent with overloading. For instance, if a procedure takes two arguments, and if both these types can vary independently, then you can use overloading to ensure that both arguments are converted to a common type.

    procedure foo;
    
    [T1,T2]
    overload foo(a:T1, b:T2) {
        // by default, convert both arguments
        // to the type of first argument.
        foo(T1(a), T1(b));
    }
    
    // the following overload specializes for the case
    // when both arguments are of the same type.
    [T]
    overload foo(a:T, b:T) {
        ...
        implement the logic here
        ...
    }