Issue #7701 has been updated by prijutme4ty (Ilya Vorontsov).


trans (Thomas Sawyer) wrote:
> So, in ((*real code*)), you ((*will*)) be looking at some file hidden far in a thirdparty gem, trying to understand what required keyword arguments you need to use. Thus the above use of required keywords gains us nothing over:
> 
>     def send(text, sender, recipient)
> 
> except more typing on the caller side.

In case of keyword arguments you immediately get an exception (and code can be verified even before it was run). 
You need not only to write code but also to read. And in this case you can understand intention of code without looking at documentation. Probably a bit more time for writing code but much less time to read and understand.
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Feature #7701: Non-optional (required) keyword args
https://bugs.ruby-lang.org/issues/7701#change-37575

Author: headius (Charles Nutter)
Status: Assigned
Priority: Normal
Assignee: nobu (Nobuyoshi Nakada)
Category: 
Target version: 


=begin
I would like to see keyword args expanded to include a non-optional form, to force callers to pass in keyword arguments.

Currently, we have required, optional, and rest positional args but only optional and rest keyword args. Consistency is one small reason to add required keyword args.

They would likely take the form of keyword with no default value:

  def foo(a:, b:)
    ...
  end

  foo(a: 1, b: 2) # ok
  foo(a: 1) # ArgumentError

Justifications:

* Consistency with positional args. A weak justification, I know.
* Avoiding a lot of boilerplate code by users wishing to enforce keywords being passed in. Example from tenderlove:

    def foo(a: raise('pass a'), b: raise('pass b'))

* Building a rich API atop keyword args would be easier (i.e. require fewer manual checks) if you could force some keywords to be passed in. Having to check everywhere when you require a keyword argument is unpleasant.
* Keyword args already enforces that no *additional* keyword args can be passed (without **), and it seems lopsided to have no way to enforce a minimum set of keyword args.
=end



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