The beauty of go is YAGNI. Language design makes it much harder for people so do stupid and cute things.
During my design process if I start realizing that I’m missing maps, More expressive Types, Or more complex polymorphism. I ask myself if I really need those things.
If I really do. I move off of go.
That’s the beauty of the language. Go does not need more complicated language features because it’s can handle the majority of trivial software work without unnecessary complexity.
The language does not need to solve complicated problems.
Ok, and what if you realize you want these things a million lines in? Do you still move off of Go?
Generic programming isn’t some fancy research language feature like dependent types. It’s just a bare minimum feature in any modern typed language.
It’s perplexing that after C# and Java both notably shipped without generics initially then added them later that they decided to ship Go without generics.. only to end up adding them later.
I guess it's possible that C# and Java taught the wrong lesson (you can add this later) and that actually reduced the impetus to ensure Go shipped generics in 1.0
It is also entirely fair to say there's a lot of complexity here and so there's a risk you exceed your complexity budget which for Go as I understand it was very slim. It is a possible a Go 1.0 with more generics doesn't take off because too many people bounce off the extra complexity and so a decade later it's an obscure thing Google made once that has a few fans but not much adoption.
Or that extra complexity means Go 1.0 ships five years later, after Rust 1.0 has given people an appetite for better performance and better safety and its sharpest corners have already been knocked off.
From what I've seen, I don't think the core Go team was ignoring the lessons of Java or C#.
Here's a sample quote from Russ Cox from 11 years ago on this site: [1]
We have spoken to a few true experts in Java generics and each of them has said roughly the same thing: be very careful, it's not as easy as it looks, and you're stuck with all the mistakes you make. As a demonstration, skim through most of http://www.angelikalanger.com/GenericsFAQ/JavaGenericsFAQ.ht... and see how long before you start to think "was this really the best way to do this?"
And of course, they asked other experts for help, including Philip Wadler (of Featherweight Java and Haskell fame): [2] [3]
We’ve been thinking about generics since work on Go began, and we wrote and rejected our first concrete design in 2010. We wrote and rejected three more designs by the end of 2013. Four abandoned experiments, but not failed experiments, We learned from them, [...]
Last year [2018] we started exploring and experimenting again, and we presented a new design [...] and we’ve been working with programming language theory experts to understand the design better.
FWIW, C# generics are way better (ergonomics) than the Java ones (due to type erasure), so Java waited too much. History is more complicated though for Java, since it was either having some generics vs having none. See [this](https://softwareengineering.stackexchange.com/questions/1766...) for a lengthier discussion.
Yes, .NET had the benefit of coming second and using F#, which was originally essentially OCaml 4 on .NET, as it's testing grounds. Same for Async
I am considering .NET for one of my compilers backends because of the reified generics. .NET can even pass around an object with generic methods that get specialized via JIT at runtime each time it sees a new data type (with reference types sharing implementations). Which also ties back to having true value types
It's a shame it took so long for .NET core to come around because even today the platform carries a reputation for being windows first which hasn't really been true for many years now
People always forget this other post when arguing for the home team.
"They are likely the two most difficult parts of any design for parametric polymorphism. In retrospect, we were biased too much by experience with C++ without concepts and Java generics. We would have been well-served to spend more time with CLU and C++ concepts earlier."
It doesn't seem particularly damning to me, though, especially written by Russ Cox in hindsight. It's almost a truism that if you had spent less time on approaches that didn't pan out and more time on approaches that did eventually pan out, you likely would have arrived at a workable solution sooner.
For example, if the core Go team had spent more time exploring C#-like approaches (as some suggest they should have), it's possible that would have delayed the whole thing.
(btw, consider me a "long time listener, first time caller" -- I pretty much always pause to read your comments while flicking through discussions here, including I appreciate you often bring in historical context, even if I might have a different take, or even if I might have expressed your take differently ;)
I'd welcome the ternary conditional operator but I hope exception handling never gets introduced (at least as I'm used to it from Java, C#, JS, etc.).
Exceptions should not be conflated with regular error handling, especially when they're allowed to bubble up from anywhere. I very much appreciate that functions that can return errors force the caller to deal with them, for the most part. True exceptions can already be thrown with panic, although I actually find it incredibly rare that I need to reach for that tool. I'd argue that when people talk about exceptions they almost always actually want "unhappy path" error handling.
Now, if Go wanted to add a sleeker way to handle those errors, similar to Rust's approach, I'd be very interested. Minimum three lines for every call to a function that returns an error does get a bit verbose, arguably hurting readability. A little sugar could improve readability without making error handling implicit.
So your argument is that they should have gotten it exactly right first time and stuck to their guns?
I mean come on. The Golang team created a useful language people use for building real things — it’s easy to work with especially on large teams, and when the lack of generics turned out to be a pain point in the end (after years of production reality) they understood what the community wanted and actually… added them..
Now what, it’s not good enough?
No one forced you to use go.
No programming language is perfect. I personally find the language has served me well.
And after being so very pro generics myself, i actually find myself not even really using them that much apart from calling the slices module etc which has them under the hood anyway…
Nope, I’m saying that the language that was seemingly designed with either an ignorance of or disdain for the hard-won lessons from decades of prior programming languages.
There was even this condescending attitude that Google engineers couldn’t understand fancy languages anyway, so they had to dumb Go down.
My criticism really isn’t even about Go itself. Yeah it’s improving, which is great.
My criticism is about this anti-intellectual attitude that has permeated the entire Go community since its inception. It’s like hearing that college is a waste of time from people who never graduated high school.
Go only took off thanks to Docker pivot from Python into Go, and Kubernetes from Java into Go, after the respective teams got some Go folks into the project.
The usual RIX approach, followed the whole devops hype cycle that created all those CNCF projects half of which no one in devops space actually knows they exist.
Map function leads to poor code in Go. Function literals are verbose and inlining is far less agressive. It simply isn't the way of the language. Even python shuns map and filter in favor of comprehensions. A for loop is more readable than the lambda soup.
I think in a language designed around FP ergonomics and expectations there's a lot to like about it.
In your second example, as a retrofit, I find myself asking "when does MapErr stop consuming the input list?", "which error gets returned if multiple errors could be returned?", "is it a errors.Joim situation", "if there are multiple errors how do I map them to the failed elements in parsed", "if I did want each parse to have either success or fail (think Result type) how would I represent this generically in a language that favours multiple return types"
There's a lot going on with that example that a for loop makes explicit and flexible for other choices.
IMO it depends on the language… to me, map/collect/etc are useful in languages that have the concept of immutable data, because you can initialize an array with a single call chain, and be sure that nothing after that can modify it.
What I’ve seen in the “for loop” approach that I can’t stand, are things like (pseudo code)
var a = []
for x in coll1 {
a.push(foo(x))
}
do_stuff_with(a)
// … further down the function
for y in coll2 {
a.push(bar(y))
}
do_other_stuff_with(a)
Reading code like that, is the first call to do_stuff_with(a) a bug, because it’s not fully built from both coll1 and coll2 yet? Or is the second call to do_other_stuff_with(a) a bug because a now contains more stuff than the developer probably thought? Can I safely move both loops next to each other, or does that break something subtle? If I need to pass a to a new function, where can I safely do this? Before or after I add from coll2? (In my actual times seeing this, a is really a map of cached key/values or something, and it’s kinda ok that the contents were different each time it was used, but subtle bugs emerged…)
IMO the sane way to do it is to just not incrementally mutate things like that, and stick with giving things a single place where they’re defined and initialized. Go doesn’t really help you here because there’s no such thing as immutable data. So just adding Map/collect or whatever doesn’t really buy you much.
Often the mutation might have performance benefits.
Of course if you're Rust the stdlib and compiler might conspire to optimise an operation you wrote which reads as non-mutating into an actual mutation which was faster.
This is another benefit of the "destructive move". If I consume X and spit out Y, the X is gone, so it's OK if secretly I just mutate X and tell you that's Y now.
map functions are very useful for iterating over collections. Most functions iterating over collections are useful, because a lot of the data you're commonly dealing with is collections. And most collections are generic.
> Function literals are verbose and inlining is far less agressive.
> Even python shuns map and filter in favor of comprehensions.
That's the problem of the language design. And Python isn't the best language to turn to for language design
> A for loop is more readable than the lambda soup.
A for loop shoving modified items into a temp variable with append() that is then returned is less readable than a map function transforming data. Too bad Go decided to turn lambdas into unreadable soup.
This is also why people eventually leave languages. Satisfy everyone’s wishes for long enough and you get lots of different styles of doing things and … «wow look at that much simpler language over there; let’s try that instead»
The fallacy of "simple" languages is not understanding the history of programming languages, why and how they grow with the community, assuming they get any adoption at all.
No one among the folks that created Scheme or C, would assert R7RS or C23 are that simple.
They threw many babies out with the bathwater chasing yhe rather unspecified "simplicity" and making parts of the lsngusge more complex to use as a result.
During my design process if I start realizing that I’m missing maps, More expressive Types, Or more complex polymorphism. I ask myself if I really need those things.
If I really do. I move off of go.
That’s the beauty of the language. Go does not need more complicated language features because it’s can handle the majority of trivial software work without unnecessary complexity.
The language does not need to solve complicated problems.