[ruby-core:99374] [Ruby master Feature#6596] New method for Arrays : Array#indexes

[ruby-core:99374] [Ruby master Feature#6596] New method for Arrays : Array#indexes

[tyler]

Issue #6596 has been updated by TylerRick (Tyler Rick).


I would really like to see this included in Ruby. I have wished for this method several times in the past, and again today.

What can I do to help move this proposal forward?

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Feature #6596: New method for Arrays : Array#indexes
https://bugs.ruby-lang.org/issues/6596#change-86780

* Author: robin850 (Robin Dupret)
* Status: Assigned
* Priority: Normal
* Assignee: matz (Yukihiro Matsumoto)
----------------------------------------
Hello

5 days ago, I submitted a pull request on Github which provides a new method for the array objects which is Array#indexes. I have fist edit the Array#index method in order it to return an array of indexes and not a single index (which is the first occurrence it finds). I found it more logical but a user (trans) tells us that it could break the contract of Array#index so I decided to move it into Array#indexes. Eric (drbrain) tells me I should reasonning why I want to add this method ; it's just a point of view : I don't really understand why Array#index return a single index if the parameter is in the array several times. 

Examples

a = [1, 2, 3, 1]
a.indexes(1)
Return : [0, 3]
a.index(1)
Return : 0
In my opinion, it's not really logical, 1 is in the array twice

Moreover, this pull request doesn't beak anything because we don't edit the Array#index method so programms which were created with previous version of Ruby will work. 

I hope my post is complete. Have a nice day.





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

[ruby-core:99377] [Ruby master Feature#6596] New method for Arrays : Array#indexes

[tyler]

Issue #6596 has been updated by TylerRick (Tyler Rick).


I'm not very good at writing C, but here is a reference implementation in Ruby (plus unit tests) in case it's helpful: https://github.com/rubyworks/facets/pull/294/files

This version adds `indexes` (aliased as `index_all`) to `Array`, `Enumerable`, and `Enumerator::Lazy` for completeness.

----------------------------------------
Feature #6596: New method for Arrays : Array#indexes
https://bugs.ruby-lang.org/issues/6596#change-86782

* Author: robin850 (Robin Dupret)
* Status: Assigned
* Priority: Normal
* Assignee: matz (Yukihiro Matsumoto)
----------------------------------------
Hello

5 days ago, I submitted a pull request on Github which provides a new method for the array objects which is Array#indexes. I have fist edit the Array#index method in order it to return an array of indexes and not a single index (which is the first occurrence it finds). I found it more logical but a user (trans) tells us that it could break the contract of Array#index so I decided to move it into Array#indexes. Eric (drbrain) tells me I should reasonning why I want to add this method ; it's just a point of view : I don't really understand why Array#index return a single index if the parameter is in the array several times. 

Examples

a = [1, 2, 3, 1]
a.indexes(1)
Return : [0, 3]
a.index(1)
Return : 0
In my opinion, it's not really logical, 1 is in the array twice

Moreover, this pull request doesn't beak anything because we don't edit the Array#index method so programms which were created with previous version of Ruby will work. 

I hope my post is complete. Have a nice day.





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

[ruby-core:99384] [Ruby master Feature#6596] New method `Array#indexes`

[sawadatsuyoshi]

Issue #6596 has been updated by sawa (Tsuyoshi Sawada).


TylerRick (Tyler Rick) wrote in #note-23:
> What can I do to help move this proposal forward?

Provide a use case.

----------------------------------------
Feature #6596: New method `Array#indexes`
https://bugs.ruby-lang.org/issues/6596#change-86791

* Author: robin850 (Robin Dupret)
* Status: Assigned
* Priority: Normal
* Assignee: matz (Yukihiro Matsumoto)
----------------------------------------
I submitted a pull request on Github that provides a new method `Array#indexes`. It departs from `Array#index` in such a way that it returns an array of indexes and not the single first occurrence that is relevant.

The reason I want this method is that I don't understand why `Array#index` returns a single index if the parameter is in the array several times. 

Examples

```ruby
a = [1, 2, 3, 1]
a.indexes(1) #=> [0, 3]
a.index(1) # => 0
```

In my opinion, it's not logical to return only a single index since `1` is in the array twice.



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