Monkey-patching metaprogramming - maybe it can be made more elegant, this is only a quick draft, and I haven't done metaprogramming for a little while...
# inject the convenience method into the definition of the Object class
class Object
def Object::bool_attr(attrname)
class_eval { define_method(attrname.to_s,
lambda { instance_variable_get('@' + attrname.to_s.chop) }) }
class_eval { define_method(attrname.to_s.chop+"=",
lambda { |x| instance_variable_set('@'+attrname.to_s.chop, x) }) }
end
end
### somewhere later
class MyClass
bool_attr :my_boolean_attribute?
def initialize
@my_boolean_attribute = true
end
end
# yet even more later
foo = MyClass.new
bar = MyClass.new
foo.my_boolean_attribute = 1
puts foo.my_boolean_attribute?
puts bar.my_boolean_attribute?
With this approach, you can be DRY and get the nice questionmark too. You just might need to pick a better name than "*bool_attr*", like, "*bool_attr_accessor*" or something similar.
The definitions that I made are a bit cranky, in a sense that the question mark is present in the original symbol. Probably a cleaner approach would be to avoid the questionmark in the symbol name and append it during the definition of the method - should be less confusing.
Oh, and almost forgot to include the obligatory link: Seeing metaclasses clearly