Labrador v0.0.1 or broken @ key


#1

Hi list

I eventually decided to submit some code to Rubyforge, just waiting
for the Rubyforge decision…

In the meantime I wanted to share some of the code to be released. It
seems that Robert K. broke his “@” key :wink: so I decided to replace
ivars in my Ruby.
Closure based properties, here we go

PropertyIllegalMonitorState = Class::new RuntimeError
class Module
def property name, type = :rw, &blk
props = {}
define_method name do
props[object_id] ||= blk.call if blk
props[object_id]
end
case type
when :rw
define_method “#{name}=” do |val|
props[object_id] = val
end
when :const
define_method “#{name}=” do |val|
raise PropertyIllegalMonitorState,
“const property #{name} cannot be reassigned” if
props.has_key? object_id
props[object_id] = val
end # define_method “#{name}=” do |val|
end
end
end

Ideas? Believes? Opinions?
Here is what I believe of it:

  • Real const properties that cannot be circumvented by metaprogramming
  • A different style never hurts
  • Quite short code to achieve this
  • Lots of place for development, locked properties to implement
    Critical Sections, access fine graining e.g.
  • Way slower than ivars I guess (no time to benchmark so far)
  • Python style property assignment on self cannot be avoided;
    self.prop = 42 not prop=42
  • You will tell me :wink:

BTW the rest of the package wil be enum trickery, things like
%w{a b c}.map.succ => %w{ b c d }
[*1…10].map(:+, 2) => [*3…12]

It is just for people who share my style (even if they do not like
Labradors;).

Cheers
Robert