Burak Serdar <[email protected]>: > Where can I read about this "implements"? Link?
https://groups.google.com/forum/#!topic/golang-nuts/pR5pmql5olM After subsequent discussion I would only add these points: * The "implements" construct is not a full generic-type system in itself, nor is it meant to be. It's meant to be an orthogonal piece that replaces heavyweight contracts proposals, and needs to be mated with a system ot parametric polymorphism and one of type composition. * To the compiler, the contract implied by each operator is just its type signature (e.g '<' has the signature a.(T).func(b T) bool) and precedence. The semantics of what each possible operator means (e.g. < is for sorting, + is a concatenation operator) is a social convention expressed by how the operator is used by the standard library and packages. * Other considerations in the language imply a rule that operators on pointer types cannot have implements methods (but non-pointer types can have implements methods with pointer receivers). * There is room for debate about which operators can be the subject of an implements clause. Everybody clearly wants < + - == | & (what you need to do set algebra) and I think ! is important. There is a general feeling that =+ =- and friends should not be overloadable but should be considered lexical abbreviations in the obvious way. * There is debate about whether there should be implied overloading - that is if a method foo(a T, b T) implements == should it be the case that not only a == b translates to foo(a, b) but a != b translates to !foo(a, b). I'm not strongly attached to a position on either of the debates. I note howvever that I do not want a < b to imply !(b > a) because I do things with graphs and lattice algebra and want to be able to express partial (not just total) ordering. -- <a href="http://www.catb.org/~esr/";>Eric S. Raymond</a> My work is funded by the Internet Civil Engineering Institute: https://icei.org Please visit their site and donate: the civilization you save might be your own. -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
