Is there any library with similar functionality like mapstruct

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1

Is there any library with similar functionality like mapstruct

2

I looked at that page, but still don’t understand what it does. Can you give a short description of what you are looking for?

3

map or merge two object

struct A
  name : String
end

struct B
  name : String
end

a = A.new "foo"
b : B = mapper.map(a)
puts b  # {name: "foo"}

b.name = "bar"

mapper.merge(a, b)

puts a # {name: "bar"}
4

I don’t think there is a shard for that.

You could quite easily do something like this with macros, though:

record A, name : String
record B, name : String

class Mapper(T)
  def self.map(x : U) forall U
    {% begin %}
      T.new(
        {% for ivar in T.instance_vars %}
          {{ ivar.name }}: x.{{ ivar.name }},
        {% end %}
      )
    {% end %}
  end
end

a = A.new "foo"
b = Mapper(B).map(a) # => B(@name="foo")
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