About the Cover

The image on the cover is a Japanese artist’s¹ illustration of an ancient Chinese legend about an Old Master who asked his disciples to describe a language that he gave them. The first student said, this language is an improvement on portable assembler. The next student said, this is a language for constructing beautiful libraries. Another student said, no, this language is for constructing hierarchies of objects. No, said the next student, this language is for expressing mathematical functions in the real world. You’ve missed its power, said another, it is for expressing generic truths about any type...

And as the students argued on, the Old Master smiled to himself.