ruby-core

Issue #15323 has been updated by Eregon (Benoit Daloze).


Isn't `enum.filter_map { |e| ... }` supposed to be (according to the name) the same as `enum.map { |e| ... }.filter { |e| e }`?

I'm not completely sure what is better, but to me it sounds surprising that a method with `filter` in its name filters differently than `Enumerable#filter` (which removes both false and nil values).

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Feature #15323: [PATCH] Proposal: Add Enumerable#filter_map
https://bugs.ruby-lang.org/issues/15323#change-81926

* Author: alfonsojimenez (Alfonso Jim駭ez)
* Status: Closed
* Priority: Normal
* Assignee: 
* Target version: 
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This is a proposal for a combined `filter` + `map` method (https://bugs.ruby-lang.org/issues/5663).

This method both filters and maps the elements of an enumerable in just one iteration:

~~~ ruby
(1..10).filter_map { |i| i * 2 if i.even? } #=> [4, 8, 12, 16, 20]
~~~

GitHub PR: https://github.com/ruby/ruby/pull/2017


 

---Files--------------------------------
0001-Adding-Enumerable-filter_map.patch (4.61 KB)


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