From: "Victor \"Zverok\" Shepelev" <vshepelev@...>
Date: 2007-09-26T22:42:23+09:00
Subject: Refactorings again: idea for library

Hi all.

Here's an idea stolen from [1] and [2].

Suppose we have a library. Suppose we've done some refactorings in it
(method or class renamed, class splitted into several, or joined, or...)

The task: change all client code in correspondence to library change.

The trick:

library/changelog.rb
---
module MyLibrary::Changelog
  version(0.2.5) do
    method_renamed [SomeClass, :method_a] => :method_b
    method_removed [SomeClass, :old_method], "he was too old"
    module_method_moved [SomeModule, :method_c] => OtherModule
    class_renamed ClassA => ClassB
  end
end
---

in code, which uses our library:

---
require 'library'
require 'library/changelog' #can omit this if you're not interested in
changes

s = SomeClass.new

s.method_a
#prints "Warning: method #method_a is renamed to #method_b. Called from
app.rb:10
#then calls s.method_b

s.old_method
#throws "Error: #old_method was removed because he was too old"
#? or prints warning and DOESN'T calls any method

SomeModule::method_c
#prints "Warning: method #method_c moved to OtherModule. Called from
app.rb:12
#then calls OtherModule::method_c

ClassA.new
#prints "Warning: ClassA renamed to ClassB. blah"
#then calls ClassB.new
---

the version(0.0.2) in example above can allow user to say
MyLibrary::ChangeLog.from_version = 0.2.1 #migrating from 0.2.1 to 0.2.5

and see only appropriate warnings.

Wha?

V.


1:
http://www.dogbiscuit.org/mdub/weblog/Tech/Programming/Ruby/RubyMethodRename
d
2: http://blade.nagaokaut.ac.jp/cgi-bin/scat.rb/ruby/ruby-talk/49730