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Generics, inheritance, and the factory pattern are completely orthogonal features. Adding generics would not entail adding inheritance, mandating the factory pattern, or any other slippery slope feature.

Most of Go's feature decisions seem to have something to do with compilation speed or how it fits in with the concurrency features and GC.

Inheritance is overrated, and the factory pattern is often overused. Both of those happen with generics.

> Inheritance is overrated, and the factory pattern is often overused. Both of those happen with generics.

Generics have nothing to do with inheritance and the factory pattern. There are lots of languages that have generics but neither inheritance neither factories: SML, OCaml, Haskell, etc.

Inheritance makes generics harder, in fact, because type inference becomes undecidable in the general case.

Factories are basically a workaround for functions not being able to be freestanding (unattached to a class) in Java (the "kingdom of nouns"), a problem that Go doesn't have.

Generics have nothing to do with inheritance and the factory pattern.

Where do I say such a thing? I'm saying that generics are both overrated and overused.

Factories are basically a workaround for functions not being able to be freestanding (unattached to a class) in Java (the "kingdom of nouns"), a problem that Go doesn't have.

Being the "Kingdom of Nouns" is kinda the point of Smalltalk/Objective-C style OO. (Though Alan Kay once famously said that when he thought of OO, he was not thinking of Java.) That said, while it is nice to have someplace to put functions, there are times when it's also nice not to be forced to attach them to a class. Not so sure it's a problem as much as it's just a particular approach with its advantages and drawbacks.

Where do you get that Factories are "a workaround for functions not being able to be freestanding?"

>> Generics have nothing to do with inheritance and the factory pattern.

> Where do I say such a thing? I'm saying that generics are both overrated and overused.

It looks like that's what you're suggesting here:

> Inheritance is overrated, and the factory pattern is often overused. Both of those happen with generics.

---

> Where do you get that Factories are "a workaround for functions not being able to be freestanding?"

A factory is, conceptually, a function of some set of inputs that returns a new instance - which is, of course, exactly what a constructor is. Now, it's not always appropriate for a class to know every single way in which it might be assembled, so such responsibility is usually lifted out - the question is where to put it. We already have constructors, and those are functions, so it would seem reasonable that we could just write method similar to a constructor, place it in some other namespace (perhaps in a completely different package/module), and then pass that along to the component that needs to create these new instances.

For languages like Java, the problem is that functions are not first class - you can't directly pass along a method/function like (Conf -> SomeService), so instead, it's common to create some special type, like SomeServiceFactory. If, for comparison, you take a look at Scala/Haskell/C#/etc, you'll wont often spot /.*Factory/ anywhere, because a function (with the ability to close over free variables) is much more concise, and doesn't require defining new types (e.g. SomeServiceFactory, versus Function<Conf,SomeService>).

I think that, seen in this light, the practice of defining dedicated factory classes is a rather clumsy approach necessitated by the design of the underlying language.

It looks like that's what you're suggesting here:

> Inheritance is overrated, and the factory pattern is often overused. Both of those happen with generics.

Non-sequitur here. To me, it's clear that I'm saying that generics are overrated and overused. Your interpretation makes no sense!

For languages like Java, the problem is that functions are not first class - you can't directly pass along a method/function like (Conf -> SomeService), so instead, it's common to create some special type, like SomeServiceFactory.

Another non-sequitur here. Factory pattern was originally popularized in the GoF book as a way of providing an opportunity for polymorphism.

If, for comparison, you take a look at Scala/Haskell/C#/etc, you'll wont often spot /.Factory/ anywhere, because a function (with the ability to close over free variables) is much more concise*

Old hand at Smalltalk here -- over 10 years. You don't often see Factory classes in Smalltalk. We also have very easy and nimble closures over variables in the context they're defined. I still don't get what you're on about.

>> Inheritance is overrated, and the factory pattern is often overused. Both of those happen with generics.

> Non-sequitur here. To me, it's clear that I'm saying that generics are overrated and overused. Your interpretation makes no sense!

Ok, now I understand what you're saying. As an aside, I would suggest that most people (as is evident in this comment thread) would not interpret your statement the way you intended.

>> For languages like Java, the problem is that functions are not first class - you can't directly pass along a method/function like (Conf -> SomeService), so instead, it's common to create some special type, like SomeServiceFactory.

> Another non-sequitur here. Factory pattern was originally popularized in the GoF book as a way of providing an opportunity for polymorphism.

I agree (re: polymorphism), but I don't think that contradicts what I'm saying; functions with parametric polymorphism (with support for {co,contra,in}variance) provide the same benefits of class polymorphism in this context.

> Old hand at Smalltalk here -- over 10 years. You don't often see Factory classes in Smalltalk. We also have very easy and nimble closures over variables in the context they're defined. I still don't get what you're on about.

You're absolutely correct. However, my point was that in statically typed languages, generics are conducive to favoring closures over factories classes and inheritance. But, now I realize that we were arguing two different things.

>Non-sequitur here. To me, it's clear that I'm saying that generics are overrated and overused. Your interpretation makes no sense!

You are making the non-sequitur. His interpretation is the only one that makes sense. It is not clear at all that you are saying what you claim you are saying. You are in fact not saying anything like it. You are saying two things you don't like happen with generics, but that is completely false.

Okay, now you just sound like you're trolling. Please point me to the grammar rule that says my referents can't be verbs.

What do you mean "now"? That was the first thing I said to you. You may wish to consider that when many people are telling you that what you said was nonsense, it may not be that all of them are crazy.

What do you mean "now"? That was the first thing I said to you.

So you are trolling, and you still haven't pointed out such a rule.

>Where do I say such a thing? I'm saying that generics are both overrated and overused.

How/why are they overused? How are they overrated? How can you claim there's any benefit to static typing but say generics are overrated?

>Inheritance is overrated, and the factory pattern is often overused. Both of those happen with generics.

No, both of those have absolutely nothing to do with "generics".

Those are all object oriented features. I was trying to compare O.O. to golang's approach.

I like the fact that you are forced to look at the algorithm vs the class hierarchy. I like that you don't have to read through factories.

I do think that generics would be great if they found a way of implementing them, however, I do not think that you need generics in order to write this kind of project.

If you generate a lot of goroutines, the overhead for maintaining and scheduling them is fairly significant, particularly when compared to constructs like Python generators.

I've demonstrated this myself by comparing the goroutines example prime number generator to a similar version written using Python generators.

The python generator code was faster, but there was a hard limit to how many primes could be calculated this way; I hit the stack limit.

[Edit] Code & times: http://pastebin.com/CqkMcxdK

>This reminds me of that one guy on the go-nuts irc channel who asked for help with his Ruby port over to Go. He was scraping a set of web pages in Ruby and migrated that over to Go for its easy parallelization. His claim was that Go was 3x slower in speed. He pasted some code that seemed fine, but left out the context of what he was doing.

Yes, with the exception of that being a story about some random idiot with an axe to grind, and this being a totally competent guy, that goes into detail about what he did and how, what trouble spots he found etc.

I guess, it being a hired project, he can't share the actual code. But he provided tons of pain points, well articulated.

The problem is that he makes a bold statement about Go's performance without proof or at least stating what the problem in Go was.

It's hard to imagine someone seriously arguing ruby is, in general, more performant than go.

I think that person was just frustrated.

This notion that having a huge gaping defect is just a different way of doing things is absurd. Lacking parametric polymorphism is completely unacceptable. This is a solved problem as of 1973. There is no excuse. Inheritance has nothing to do with it, and "all the factory code" has even less to do with it. You are saying "I like go because it isn't java", which is fine, but you are implying that being java is necessary to have parametric polymorphism, which is not at all accurate.

I like go because it's not object oriented. This forces me to read the implementation of the algorithm, not follow an abstraction hierarchy.

I like Java as well. It can be difficult to read the implementation when you are surrounded with classes. That was the point I was trying to make.

If you are thinking in generic containers and are programming in Go, you either chose the wrong language or need to change how you are thinking.

>I like go because it's not object oriented

Lots of languages are not object oriented and still have parametic polymorphism. Like SML. In 1973.

>If you are thinking in generic containers and are programming in Go, you either chose the wrong language or need to change how you are thinking.

If you are repeating the same baseless assertion routed in ignorance, then you either chose the wrong forum, or need to change how you are thinking.