Issue #11925 has been updated by Herwin W.


https://github.com/ruby/ruby/pull/1468

A proposal for an implementation.

~~~ ruby
irb(main):001:0> MyClass = Struct.new(:a, :b, :c)
=> MyClass
irb(main):002:0> MyClass.new_from_kwargs(a:1, c: 3)
=> #<struct MyClass a=1, b=nil, c=3>
irb(main):003:0> MyClass.new_from_kwargs(1, 2, 3, b: 3)
=> #<struct MyClass a=1, b=3, c=3>
irb(main):004:0> MyClass.new_from_kwargs(d: 4)
NameError: no member 'd' in struct
	from (irb):4:in `new_from_kwargs'
	from (irb):4
	from ./irb:11:in `<main>'
irb(main):005:0> MyClass.new_from_kwargs(1, 2, 4, 5, b: 3)
IndexError: offset 3 too large for struct(size:3)
	from (irb):5:in `new_from_kwargs'
	from (irb):5
	from ./irb:11:in `<main>'
irb(main):006:0> 
~~~


----------------------------------------
Feature #11925: Struct construction with kwargs
https://bugs.ruby-lang.org/issues/11925#change-61066

* Author: Ilya Vorontsov
* Status: Open
* Priority: Normal
* Assignee: 
----------------------------------------
Propose to make Struct subclass constructors which accept keyword arguments. Not sure, if it's reasonable to allow `.new` accept kwargs, so may be should use different method named like `.create`:

```ruby
  Point = Struct.new(:x,:y, :color)
  pt_1 = Point.create(x: 1, y: 2) # => Point<x: 1, y: 2, color: nil>
  pt_2 = Point.create!(x: 1, y: 2) # => ArgumentError, color not specified.
```

It will greatly simplify work with big structures, especially in cases when struct layout changes and for cases when structure can have lots of non-significant values. It also allows simpler ways to use implement default values for struct members.



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