On Wed, Jun 4, 2008 at 6:07 PM, William Stein wrote: > > On Wed, Jun 4, 2008 at 3:03 PM, Bill Page wrote: >> >> Is there any interest in also implementing the Co-product constructor? > > Yes. > >> What about Record and Union constructors? >> > > I don't know what those are (at least what Record is). >
Records and Unions are products and co-products with named projections and injections. Records are like struct in C. Unions are sometimes called "tagged-unions" but that suggests a particular implementation detail rather than an essential feature. Union is also sometimes called a "variant-record". But in my opinion the semantics is best described in more categorical terms. http://en.wikipedia.org/wiki/Record_(computer_science) http://en.wikipedia.org/wiki/Coproduct http://en.wikipedia.org/wiki/Product_(category_theory) Regards, Bill Page. --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to sage-devel@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sage-devel URLs: http://www.sagemath.org -~----------~----~----~----~------~----~------~--~---
