From: Andrew Grimm <andrew.j.grimm@...>
Date: 2011-09-21T09:25:45+09:00
Subject: [ruby-core:39647] [Ruby 1.9 - Feature #4830] Provide Default Variables for Array#each and other iterators


Issue #4830 has been updated by Andrew Grimm.


=begin
For a simple case, such as 

(({some_array.map { foo(it) }.select { bar(it) }.each { baz(it) }}))

You can do

(({some_array.map(&method(:foo)).select(&method(:bar)).each(&method(:bar))}))

instead.

> PS: Since $dollar variables are rarely used anyway, lets transform them all into special variables :D

Maybe we could migrate global variables into katakana, so we'd have local_variable, CONSTANT, $special_variables and ������!
=end

----------------------------------------
Feature #4830: Provide Default Variables for Array#each and other iterators
http://redmine.ruby-lang.org/issues/4830

Author: Lazaridis Ilias
Status: Assigned
Priority: Low
Assignee: Yukihiro Matsumoto
Category: core
Target version: 


for arrays: use "item" by default
for hashes: use "key" and "value" by default

names = ["Jane", "Michele", "Isabella"]
names.each { |name| print name, "\n" } 
names.each { print item, "\n" } 

contact = {name:"Jane", phone:"1234567"}
contact.each { |key, value| print key, ": ", value, "\n"}
contact.each { print key, ": ", value, "\n"}

-

The benefits are:

* more compact code (without loosing clarity of the code).
* no repetitions ("names, name, name") in a one-liner with {} block

This extension does not break any existent behaviour.


-- 
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