[ruby-core:102437] [Ruby master Feature#7394] Enumerable#find ifnone parameter could be non-callable

Issue #7394 has been updated by zverok (Victor Shepelev).


What's the point of the "default value" as compared to just `find { ... } || default`?

* Would it be more performant? (I believe no)
* Would it read more naturally? I believe no, the statement reads "find (and if not found, use that) by this condition..."
* Would it be readable at all?.. I believe barely, actually `find(10) { condition }` can be misunderstood as "find, starting from index 10", and something like `find(:delete) { condition }` can be read as some local DSL for "find&delete". Keyword argument will improve it, of course, but looks unlike any other core API, and still reads "find, else `default`, by this condition...".

But the question for me is still: why is it necessary at all? what exactly it achieves?

----------------------------------------
Feature #7394: Enumerable#find ifnone parameter could be non-callable
https://bugs.ruby-lang.org/issues/7394#change-90321

* Author: zzak (Zachary Scott)
* Status: Assigned
* Priority: Normal
* Assignee: nobu (Nobuyoshi Nakada)
----------------------------------------
from github:
https://github.com/ruby/ruby/pull/186

In trunk the `Enumerable#find` method `ifnone` parameter has to be callable or `nil`. I found that sometimes I want to return a simple value without wrapping it in a proc. This pull request adds support for non-callable defaults when no items match.

```ruby
a = [1, 2, 3]
```

The current behavior

```ruby
a.find(proc { :foo }) { |x| x > 3 } #=> :foo
```

With patch

```ruby
a.find(0) { |x| x > 3 } #=> 0
```


---Files--------------------------------
enumerable_find_noncallable.patch (3.45 KB)


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