Hello, This code ( https://carc.in/#/r/5whi ): class Foo end class Bar < Foo end ary = Array(Foo.class).new ary << Bar Compiles nicely, while when replacing class with module ( https://carc.in/#/r/5whj ): module Foo end class Bar include Foo end ary = Array(Foo.class).new ary << Bar It failes…

I suspect what you’ve intended to write is: https://play.crystal-lang.org/#/r/5wp0 module Foo end class Bar include Foo end ary = Array(Foo).new ary << Bar.new() p! ary

No, I’m absolutely sure that I need to store classes, not their instances.

Probably not intended nor designed. I don’t recall any story about the metaclass design related to modules and classes that are including them. What is what you are trying to achieve later with that array?

There are two things here. First, it’s OK for the code not to compile because when you include a module only the instance type gets included, so technically the Bar class is not a Foo class. You can see this is like that because you can’t invoke class methods of Foo from Bar. module Foo def self.…

[image] asterite: so technically the Bar class is not a Foo class That’s interesting. However, even when extending, it doesn’t work as well ( Carcin ): module Foo end class Bar extend Foo end ary = Array(Foo.class).new ary << Bar Error in line 9: no overload matches 'Array(Foo:Module)#<<'…

Okay, as always, after posting I understand that module would not work for me in my case because all_subclasses for a module doesn’t make sense. And I need to know subclasses for my arch. However, the issue still remains, and I cannot use a module Foo's includer in the place of Foo.class.

Array co-something inconsistency

Help & Support

vladfaust January 3, 2019, 4:22pm 8

How about Array(Foo.module)?

T is not a subclass of Exception

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Array co-something inconsistency

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