Feature #15374
closedProposal: Enable refinements to `#method_missing`
Description
Proposal enable refinements to #method_missing
.
It can be used in the following cases.
# Access key value with method
using Module.new {
refine Hash do
# name is Symbol or String
def method_missing(name)
self[name.to_sym] || self[name.to_s]
end
end
}
hash = { name: "homu", "age" => 14 }
pp hash.name
# => "homu"
pp hash.age
# => "age"
method_missing
is hard hacking.
I would like to use Refinements with method_missing
.
pull request: https://github.com/ruby/ruby/pull/2036
Updated by Hanmac (Hans Mackowiak) over 3 years ago
i always like the fun you can do with method_missing, but for your example, method_missing always use a symbol for the name, so name.to_sym should just return self or did you do that on purpose?
Updated by osyo (manga osyo) over 3 years ago
oops, that's right.
Updated by Eregon (Benoit Daloze) over 3 years ago
This wouldn't work, e.g. for hash.first
, or any existing method of Hash
.
Can you show a use case for this feature?
Updated by osyo (manga osyo) over 3 years ago
Yes, it will be the specification of Ruby.
method_missing has a large side effect.
So can use using
to control by context.
module HashWithAsscessKeyToMethod
refine Hash do
# name is Symbol or String
def method_missing(name)
self[name] || self[name.to_s]
end
end
end
# Do not want to use Hash#method_missing
hash = { name: "homu", age: 14 }
pp hash[:name] # OK
# pp hash.name # NG
# Do want to use Hash#method_missing
using HashWithAsscessKeyToMethod
pp hash.name # OK
User can choose.
Updated by matz (Yukihiro Matsumoto) over 3 years ago
- Status changed from Open to Rejected
I don't see any real-world usage of allowing #method_missing
refinable. Maybe it can be used only for tricks and obfusticated code.
Matz.
Updated by osyo (manga osyo) over 3 years ago
OK, Thanks matz :)