[ruby-core:46783] [ruby-trunk - Feature #6687] Enumerable#with

< ^ > P N |<>| ^ _>< --- | ~ ...Help
Issue #6687 has been updated by merborne (kyo endo).


nobu (Nobuyoshi Nakada) wrote:
> I don't think "with" is nice as a method name.
> What does it `with' the argument?
> "each" should not be omitted, I guess.

It iterate(or enumerate) with the argument. The receiver, by itself tells it, I think.
I think #each tells nothing. it suggests the returning value is `self` instead.
This method returns a passed object...

How about #return_with ?

----------------------------------------
Feature #6687: Enumerable#with
https://bugs.ruby-lang.org/issues/6687#change-28453

Author: merborne (kyo endo)
Status: Open
Priority: Normal
Assignee: 
Category: 
Target version: 


=begin
Let me propose `Enumerable#with` for an alias of `Enumerable#each_with_object` or replace of it.

`Enumerable#each_with_object`??Ўу?Ју?Єу?Њу?Ђу?Йу????Оу????Џу????ЎчНЎ???????????Ју????Іу??`Enumerable#with`??????цЁ??????Оу?????

##Reason

##??????

When you create a hash using `Enumerable#inject`, you should ensure that the block return the hash.

`Enumerable#inject`???фНПу?Ѓу?Іу??????Зу?Ѕу????????????????Ју????Ћу?Џу???????у????Џу?Ўш???????Єу?Ју????Іу??????Зу?Ѕу??шП?????????Ју??фП?шЈМу?????хП?шІ????????????Оу?????

    words.inject(Hash.new(0)) { |h, word| h[word] += 1; h } # => {"You"=>3, "say"=>10, "Yes"=>1, "I"=>7, "No"=>1, "Stop"=>1, "and"=>2, "Go"=>1, "go"=>2, "Oh"=>1, "no"=>1, "Goodbye"=>2, "Hello"=>2, "hello"=>5, "don"=>2, "t"=>2, "know"=>2, "why"=>2, "you"=>2, "goodbye"=>1}

Many rubyists, however, hate this, and there are many discussions for it.

?????????????????????хЋ????Rubyist??Џх????????????????фИ???Їу????Ўц?Йх????Ћу?Єу????Іу?ЎшАшЋ?????????Ау????Аш??????????Оу?????

    Feature #5662: inject-accumulate, or Haskell's mapAccum* - ruby-trunk - Ruby Issue Tracking System http://bugs.ruby-lang.org/issues/5662
    
    Ruby inject with intial being a hash - Stack Overflow http://stackoverflow.com/questions/9434162/ruby-inject-with-intial-being-a-hash

`Enumerable#each_with_object` is often presented for one of the best solutions for it.

????????Іу????Ўц???????ЊшЇЃцБКч????Ју????Іу??Enumerable#each_with_object??????чЄКу???????Іу????Оу????????

    words.each_with_object(Hash.new(0)) { |word, h| h[word] += 1 } # => {"You"=>3, "say"=>10, "Yes"=>1, "I"=>7, "No"=>1, "Stop"=>1, "and"=>2, "Go"=>1, "go"=>2, "Oh"=>1, "no"=>1, "Goodbye"=>2, "Hello"=>2, "hello"=>5, "don"=>2, "t"=>2, "know"=>2, "why"=>2, "you"=>2, "goodbye"=>1}

However, `each_with_object` is still unfamiliar and then not used frequently. The biggest reason, I think, is its lengthy name.

?????????????????Ўц????Јц?Їу?Ћу??????????????фО???Жу?Ју?????each_with_object??Ўч?Ѕх??хКІу???????Гх?Љч?Јщ?ЛхКІ??Џф?????Јц?????????Оу?????????????Іу???????Ўх???????Џу???????Ўх???????Ўщ?Зу????Ћу???????Јш???????Оу?????

`each_with_object` is the 39th longest-name method among 754 at Ruby 1.9.3, based on following calculation;

фЛЅф????Ўц??чЎ???Ћу????????Ruby1.9.3??Ўч?Ах??фИ????each_with_object??Џу??754фЛЖфИ39??Њч?Ўу?Ћщ?Зу??????????Ўу?Ёу?Ну???????Їу??????????Ју?????????????Оу????????

    methods = Module.constants.flat_map do |c|
      next [] if c == :Gem
      k = Module.const_get(c)
      k.methods(false) + k.instance_methods(false) rescue []
    end.uniq.reject { |m| "#{m}".start_with? '_deprecated' }.sort_by { |m| -m.size }
    
    methods.size # => 754
    methods.index(:each_with_object) # => 39
    
    puts methods.take(100).group_by(&:size).to_a

The output is here.

??Кх????Їу?????

    26
    protected_instance_methods
    instance_variable_defined?
    25
    protected_method_defined?
    24
    private_instance_methods
    23
    class_variable_defined?
    public_instance_methods
    define_singleton_method
    private_method_defined?
    22
    singleton_method_added
    public_instance_method
    public_method_defined?
    21
    instance_variable_get
    instance_variable_set
    remove_class_variable
    20
    private_class_method
    repeated_combination
    repeated_permutation
    compare_by_identity?
    19
    respond_to_missing?
    abort_on_exception=
    public_class_method
    compare_by_identity
    18
    undefine_finalizer
    instance_variables
    abort_on_exception
    class_variable_get
    class_variable_set
    relative_path_from
    17
    internal_encoding
    external_encoding
    default_internal=
    default_external=
    protected_methods
    singleton_methods
    ascii_compatible?
    16
    global_variables
    executable_real?
    initialize_clone
    each_with_object   # <= Here!
    require_relative
    private_constant
    default_external
    included_modules
    instance_methods
    define_finalizer
    default_internal
    15
    private_methods
    fixed_encoding?
    class_variables
    instance_method
    each_with_index
    public_constant
    garbage_collect
    source_location
    valid_encoding?
    singleton_class
    world_writable?
    local_variables
    world_readable?
    method_defined?
    14
    readable_real?
    locale_charmap
    const_defined?
    collect_concat
    initialize_dup
    add_trace_func
    close_on_exec=
    close_on_exec?
    named_captures
    set_trace_func
    write_nonblock
    writable_real?
    each_codepoint
    force_encoding
    public_methods
    13
    const_missing
    each_filename
    default_proc=
    set_backtrace
    public_method
    read_nonblock
    instance_exec
    absolute_path
    count_objects
    instance_eval
    12
    marshal_load
    reverse_each
    exclude_end?
    instance_of?
    make_symlink
    set_encoding
    block_given?
    default_proc
    slice_before
    marshal_dump
    11
    rationalize
    realdirpath
    each_object
    expand_path
    with_object

This result shows that methods which has 15+ name length is mostly for reflection or for special purpose. `each_with_object` is a general purpose method, the name should be shorter. 

?????Ўу?Њу?Йу??????????????????????Ју?Џу????Зу??15???шЖ?????????Ёу?Ну???????Џу????ЎхЄЇ????????Њу????Ќу?Џу?Зу?Їу?Гч?Ју????Йц????Ўч????Ју?Ўу????Ўу?Їу???????Ју?????фК?хЎ???Їу?????each_with_object??Џу?????цБ?Јч????Њу?Ёу?Ну???????Їу????????????????Ўх???????Џу????Ѓу?Јч?у?????????Йу????Јш???????Оу???????Жу?Ўщ?Зу????Џу???????Ўу?Ёу?Ну??????????Ёу???????Ўу?Ћу????Іу????Оу?????

I propose Enumerable#with for it. a word `object` in `each_with_object` is obvious and not necessary to spcify the purpose, because all data in Ruby is `object`. Also, a word `each` in `each_with_object` is not essential, then omittable in view of the fact that it is called to Enumerable object. I think that a word `with` still works for describing the same of `each_with_object`.

?????????Enumerable#with??????цЁ??????Оу???????Оу?????Ruby??Їц?Бу????????????Му?Пу?Џу????Йу?Іу?Њу????Иу?Їу?Џу????Їу???????????each_with_object??Ћу????????object??Џш?Њц??Їу?????фИ?шІ???Јш???????Оу?????цЌЁу?Ћу??Enumerable??Њу????Иу?Їу?Џу????ЋхЏО????????Ёу?Ну???????Му?Гх?Ку????Ју???????Йу?????шІ???Іу??each???хП??????Ўу????Ўу?Ју?Џш????????????????Єх?Ну?Јш???????Оу?????????????Іц????Ѓу??with??Їх???????Ћу????Ўч?Ўч???????Єу?Оу??Enumerable??Њш??чД????фЛЛц???Ўу?Њу????Иу?Їу?Џу????Јх?Бу?Ћц??фН?????????????????Гу?Їу????Іу???????Јш???????Оу?????

Lastly, following is examples with `Enumerable#with`

???хО???Ћу??`Enumerable#with`???фНПу?Ѓу??фО????чЄКу????Оу?????

    Enumerable.send(:alias_method, :with, :each_with_object)

    words.with(Hash.new(0)) { | word, h| h[word] += 1 } # => {"You"=>3, "say"=>10, "Yes"=>1, "I"=>7, "No"=>1, "Stop"=>1, "and"=>2, "Go"=>1, "go"=>2, "Oh"=>1, "no"=>1, "Goodbye"=>2, "Hello"=>2, "hello"=>5, "don"=>2, "t"=>2, "know"=>2, "why"=>2, "you"=>2, "goodbye"=>1}

    [*1..10].with(5).map(&:*) # => [5, 10, 15, 20, 25, 30, 35, 40, 45, 50]
    
    ['ruby', 'python', 'haskell'].with('ist').map(&:+) # => ["rubyist", "pythonist", "haskellist"]


Thank you for your consideration.

???цЄ?шЈ?Ўч????????????????щЁ??????Ду????Оу?????

=end



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