Issue #14580 has been updated by Eregon (Benoit Daloze).


mame (Yusuke Endoh) wrote:
> We need to keep a flag if rehash occurred or not during the block executed.

Also, what should happen with:

~~~ruby
hash.store(:a) { |v| hash.delete(:a); v + 42 }
~~~

"store" starts to feel to me like the wrong name, it sounds more like an "update" of an existing key (but Hash#update is an alias of Hash#merge!).

----------------------------------------
Feature #14580: Hash#store accepts a block
https://bugs.ruby-lang.org/issues/14580#change-70908

* Author: Soilent (Konstantin x)
* Status: Open
* Priority: Normal
* Assignee: 
* Target version: 
----------------------------------------
Given a hash

~~~ ruby
hash = { a: 2 }
~~~

I want to update a single value in the hash:

~~~ ruby
hash[:a] = hash[:a] + 42
hash[:a] #=> 44
~~~

But instead, I would like to have a method that yields the current value for a given key and associates the block result with the key (similar to Hash#update). I think that Hash#store can be extended to support a block arg.

~~~ ruby
hash.store(:a) { |val| val + 42 }
hash[:a] #=> 44
~~~

Or it can be something like this:

~~~ ruby
hash.transform_values(:a, :b) { |val| val + 42 }
hash[:a] #=> 44
~~~



-- 
https://bugs.ruby-lang.org/

Unsubscribe: <mailto:ruby-core-request / ruby-lang.org?subject=unsubscribe>
<http://lists.ruby-lang.org/cgi-bin/mailman/options/ruby-core>