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I bet I could do those as getters and set them in the initializer, though.
That is, you can't have constants have different values depending on T
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Plus you can't do
Indigent(Int32)::MAX (I think that doesn't even parse)
Hello, I have this code:
class Animal
end
class Cat < Animal
def meow
puts "meow!"
end
end
class Dog < Animal
def woof
puts "woof!"
end
end
animals = Hash(Animal.class, Hash(Int32, Animal)).new { |h, k| h[k] = Hash(Int32, Animal).new }
animals[Cat][1] = Cat.new
animals[Dog][1] = Dog.new
animals[Dog][1].as(Dog).woof
animals[Cat][1].as(Cat).meow
dogs = animals[Dog].as(Hash(Int32, Dog))and I'm getting an error on the last line:
23 | dogs = animals[Dog].as(Hash(Int32, Dog))
^
Error: can't cast Hash(Int32, Animal) to Hash(Int32, Dog)I don't understand why casting an element in the hash works, but casting the whole hash doesn't? Are there alternatives to what I'm trying to achieve (essentially index objects by type & by id)?
straight-shoota: Why does Shardbox have roughly 1/6 of the shards as some of the other databases? Yours is my favorite still though
and because is typed as
Animal that would be possible
In this particular case, you could use
dogs = animals[Dog].transform_values &.as(Dog) on your last line.
I want to store objects based on their type & id in a hash
all objects would inherit from some class, so it made sense to me to use
Hash(Animal.class, Hash(Int32, Animal)) as type definition
<riza> Hash(Animal.class, Array(Animal))
like
cat.id
object with id = 2 only has a cat
while object with id = 3 has an opposum
there could potentially be >100 type of objects, I don't really want to define 100 properties on struct
and same for ids
Oh, but you need to be able to retrieve all dogs and cats, I see...
So it's a long shot but figure I'll ask anyway: My biggest problem seems to be trying to come up with an ordering that compiles with regard to
requireing the proper files where they are needed. It seems to get really confused sometimes when I include or extend a module. I sort of wish I could just require "./project/* in a project.cr file in src/, but a real solution seems to be repeating the same requires in different files. I have no idea what I'm doing wrong, if anything, because I'm really not used to programming in such an OOP way, and mixins even less so. Has anyone ran into these sorts of problems before, and how did you get used to it/find something that works? Can anyone recommend some tutorials for Crystal or Ruby or similar for structuring a project in a nice way?
Also sometimes it blows up when I use
include by itself, and I have to wrap it in macro included fairly often.
It's quite maddening, because I don't see anything wrong with a fairly simple project.
That's what I first tried, and infact I'm reading that file right now lol
that covers most things, are still a few cases where i may need to require something in a specific file. For example the exceptions dir, most of them require
http_exception i could have prob added that as a one off require before the directory but :shrug: didn't think it was worth it
so i guess tl;dr is like, global things in main file, then sometimes specific requires within directories as needed
Also sometimes it blows up when I use
includeby itself, and I have to wrap it inmacro includedfairly often.
got an example of this?
So would you say that you recommend explicitly listing every file and very rarely use the glob except for collections of order independent submodules?
I have always preferred to do a serial load order myself in Lisp, manually toposorting it as I develop so that sounds like what I prefer