Issue #15381 has been updated by Dan0042 (Daniel DeLorme).
There are certainly backwards compatibility issues from changing `**` from calling `to_hash` to `to_h`.
What kind of backwards compatibility issues exactly? My idea was to call #to_hash and fall back to #to_h, that should ensure no backwards incompatibility at all, unless I'm missing something?
Using the unary `**` operator on an object would call the `**@` method, which should return a hash (or raise an exception).
That's a very intriguing solution, and very elegant I have to say. ---------------------------------------- Feature #15381: Let double splat call `to_h` implicitly https://bugs.ruby-lang.org/issues/15381#change-110213 * Author: sawa (Tsuyoshi Sawada) * Status: Open ---------------------------------------- The single splat calls `to_a` implicitly on the object (if it is not an array already) so that, for example, we have the convenience of writing conditions in an array literal: ```ruby a = [ *(:foo if some_condition), *(:bar if another_condition), ] ``` And the ampersand implicitly calls `to_proc` on the object (if it is not a proc already) so that we can substitute a block with an ampersand followed by a symbol: ```ruby some_method(&:some_method_name) ``` Unlike the single splat and ampersand, the double splat does not seem to implicitly call a corresponding method. I propose that the double splat should call `to_h` implicitly on the object if it not already a Hash so that we can, for example, write a condition in a hash literal as follows: ```ruby h = { **({a: 1} if some_condition), **({b: 2) if another_condition), } ``` There may be some other benefits of this feature that I have not noticed yet. -- https://bugs.ruby-lang.org/