can_has_meta

this gem is meta

Author

Ben Burkert (ben@benburkert.com)

Version

0.1.0

Copyright

Copyright © 2008 Ben Burkert. All rights reserved.

License

New BSD License (opensource.org/licenses/bsd-license.php)

Website

canhasgems.rubyforge.org/can_has_meta

Repository

git://github.com/benburkert/can_has_meta.git

Dependencies

Basic Usage

can_has_meta adds three new items to your meta programming toolshed.

Object#instance_eval(*args, &block)

instance_eval has been modified to allow parameters to the block:

"abc".instance_eval("def") do |s|
  p self << s  # => "abcdef"
end

Module#macros(&block)

macros evaluates the block in the including class’s class, got it? Basically, it makes it super easy to add “acts_as_*” style methods:

module Foo
  macros do
    def acts_as_foo
      def baz
        "FOO-BAR-BAZ!"
      end
    end
  end
end

class Bar
  include Foo

  acts_as_foo
end

p Bar.new.baz # => "FOO-BAR-BAZ"

Module#mixins(&block)

mixins evaluates the block in the including class’ instance. This allows you to manipulate the type including the module directly.

module Foo
  p self

  mixins do
    p self

    def foo_bar_baz; end
  end
end
#   => Foo

module Bar
  include Foo
end
#   => Bar

class Baz
  include Bar
end
#   => Baz