(class-or) ( first second -- class )

Vocabulary

classes.algebra.private

Inputs

first	an object
second	an object

Outputs

class

an object

Definition

USING: classes.algebra combinators kernel math.order ;

IN: classes.algebra.private

: (class-or) ( first second -- class )
    2dup compare-classes {
        { +lt+ [ nip ] }
        { +gt+ [ drop ] }
        { +eq+ [ nip ] }
        {
            +incomparable+
            [
                {
                    { ~quotation~ ~quotation~ }
                    { ~quotation~ ~quotation~ }
                    [ classes>anonymous-union ]
                } cond
            ]
        }
    } case ;