The syntax has waaaay too many options. This leads to a language where 3rd party tools are really hard to write. Even at this late date, refactoring tools are mostly absent (or awful). Not only that, but it leads to serious religious wars about how to format your code (I'm sick to death of it, even though I try to stay out of it).
Modules are slightly strange. You can't really use them for namespacing without writing pretty non-standard code. They are really only useful for mixins -- which normally isn't a great plan.
And as popular as meta programming is, it's incredibly awkward. The underlying design seems completely arbitrary and is hard to reason about. Despite the many syntactic options for frivolous things, there are very few syntactic tools for meta programming -- just super long function names.
People are going to laugh, but I actually prefer Javascript to Ruby because the design is much more logical and flexible (despite the poor syntax and really terrible standard library). There are lots more things that bug me about Ruby, but I think those are the main ones. I still enjoy writing code in it, but it wouldn't be my first choice these days.
The Ruby community likes things that think for you, and insert methods unexpectedly, change the meaning of semantics, and all sorts of other magic designed to think for the programmer.
But macros? A language with macros I'm working with is Elixir. Even the seldom used if then else is a macro there. Do people dislike Elixir because macros change the code at compile time? I don't think so.
Then what would you call the method_missing method?
> a b c
> = Name Error
> def method_missing(*args); args.join(" "); end
> a b c
> = "a b c"
That looks exactly like a macro to me.
---
> But macros?
Not macros as such, we all like having them. But Ruby likes using them constantly, and that culture is hardly restricted to Rails.
> Macro is a great power, but at the same time, it makes the languagesyntax different for each application. You will have hard time to read the program without knowledge of the application/framework macros.
> So I am not going to add macro to Ruby.
> matz.
https://www.ruby-forum.com/topic/215212
The funny thing is that this is what happens when we use method_missing or other Ruby features to create DLSes: unless you know the application/framework DLS you can't understand the program. They must be used wisely.
But to be fair: how can one understand a program without the knowledge of the non standard libraries it uses? This applies to every program and language, macros or not.
> Don't bother developers with macros when they aren't writing one: the language's syntax and semantics should be best suited for those 95% of the time when we aren't writing macros.
An extended language to add more magic, says we don't need it most of the time.
And to be honest, it's one of the things about the Lua community I find really attractive.