From: Daniel Berger <djberg96@...>
Date: 2008-03-08T13:18:23+09:00
Subject: Re: fattr-1.0.2



On Mar 7, 9:08 pm, ara howard <ara.t.how...@gmail.com> wrote:
> NAME
>    fattr.rb
>
> INSTALL
>    gem install fattrs
>
> URIS
>    http://codeforpeople.com/lib/ruby
>    http://rubyforge.org/projects/codeforpeople/
>    http://codeforpeople.rubyforge.org/svn/
>
> SYNOPSIS
>    fattr.rb is a "fatter attr" for ruby.
>
>    fattr.rb supercedes attributes.rb as that library, even though it
> added only
>    one method to the global namespace, collided too frequently with
> user code -
>    in particular rails' code.
>
>    the implementation of fattr.rb borrows many of the best ideas from
> the
>    metakoans.rb ruby quiz
>
>      http://www.rubyquiz.com/quiz67.html
>
>    in particular the solutions of Christian Neukirchen and Florian
> Gross along
>    with concepts from the original traits.rb lib
>
>    key features provided by fattrs are
>
>      - ability to specify default values for attrs and definition
> time.  values
>        can be literal objects or blocks, which are evaluated in the
> context of
>        self to initialize the variable
>
>      - classes remember which fattrs they've defined and this
> information is
>       available to client code
>
>      - a whole suite of methods is defined by calls to #fattrs including
>       getter, setter, query (var?) and banger (var! - which forces
>       re-initialization from the default value/block)
>
>      - ability to define multiple fattrs at once using key => value
> pairs
>
>      - fast lookup of whether or not a class has defined a certain fattr
>
>      - fattrs can be defined on objects on a per singleton basis
>
>      - getters acts as setters if an argument is given to them
>
>      - block caching, calling an fattr with a block sets the instance
>        variable to that block
>
>      - shortcuts for adding class/module level fattrs
>

Interesting. What about data types?

class C
   fattr 'a' => Integer
end

c = C.new
c.a = 42 # ok
c.a = 'hello' # TypeError

You may have this, but I didn't see it in the samples or readme (but
very well may have missed it).

Regards,

Dan