Issue #17097 has been updated by universato (Yoshimine Sato).


https://github.com/crystal-lang/crystal/pull/365
In Crystal language, these proposed methods are called `max_of`, `min_of`.
Note: Crystal has `max`, `max_by`, `max_of`.

This feature may not be innovative, but I think many Ruby users have the opportunity to use these methods.

----------------------------------------
Feature #17097: `map_min`, `map_max`
https://bugs.ruby-lang.org/issues/17097#change-89893

* Author: sawa (Tsuyoshi Sawada)
* Status: Open
* Priority: Normal
----------------------------------------
`min`, `min_by`, `max`, `max_by` return the element that leads to the minimum or the maximum value, but I think it is as, or even more, frequent that we are interested in the minimum or the maximum value itself rather than the element. For example, to get the length of the longest string in an array, we do:

```ruby
%w[aa b cccc dd].max_by(&:length).length # => 4
%w[aa b cccc dd].map(&:length).max # => 4
```

I propose to have methods that return the minimum or the maximum value. Temporarily calling them `map_min`, `map_max`, they should work like this:

```ruby
%w[aa b cccc dd].map_max(&:length) # => 4
```

`map_min`, `map_max` are implementation-centered names, so perhaps better names should replace them, just like `yield_self` was replaced by `then`.



-- 
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>