Does anyone know how can I override ruby’s Array delete method, and
use my own instead?
Cheers,
Michal
Hi –
On Fri, 20 Jul 2007, michau wrote:
Does anyone know how can I override ruby’s Array delete method, and
use my own instead?
class Array
def delete(obj)
…
end
end
However, it doesn’t sound like a good idea, as you’ll be clobbering a
core method. You’d probably be better off doing something like:
module MyArray
def delete(obj)
…
end
end
a = [].extend(MyArray)
David
–
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michau wrote:
Does anyone know how can I override ruby’s Array delete method, and
use my own instead?Cheers,
Michal
Sure you want to do that ? 
I think it’s as easy as:
Class Array
def delete(object)
your_code
end
end
I might be forgetting something…
put the following into lib/helpers.rb (or some other file in /lib) and
then put: require ‘lib/helpers.rb’ into your environment.rb. Put the
following into your helpers.rb file:
class Array
def delete(*arg, &block)
do my stuff
end
end
Adam
Sure you want to do that ?
I’m not sure. The rails method generated by has_many declaration
returns an Array though, right?
I want to be able to delete from that array, effectively destroying
rows in the database through a call like
@returned_array_of_my_objects.delete {|object| object.name == “name”}
Michal
there’s an easier way of doing that…
article.rb
has_many :users
users = @some_article.users
users.each {|user| user.destroy if user.name == “delete me”}
On Jul 20, 2007, at 3:27 PM, michau wrote:
Sure you want to do that ?
I’m not sure. The rails method generated by has_many declaration
returns an Array though, right?
I want to be able to delete from that array, effectively destroying
rows in the database through a call like
@returned_array_of_my_objects.delete {|object| object.name == “name”}Michal
Although it masquerades as an Array, the result of a has_many
association is actually an association proxy that still mixes in a
large amount of ActiveRecord goodness.
From a handy script/console session:
Here’s a has_many association: (see the @macro instance variable)
User.reflect_on_association(:favorites)
=> #<ActiveRecord::Reflection::AssociationReflection:0x3312290
@options={:dependent=>:destroy, :include=>:product},
@class_name=“Favorite”, @active_record=User, @klass=Favorite,
@macro=:has_many, @primary_key_name=“user_id”,
@through_reflection=false, @name=:favorites>
The favorites say they are what?
User.find(1).favorites.class
=> Array
Oh, really?
User.find(1).favorites.ancestors
=> [Favorite, ActiveRecord::Base, ActiveRecord::AttributeMethods,
ActiveRecord::XmlSerialization, ActiveRecord::Calculations,
ActiveRecord::Acts::NestedSet, ActiveRecord::Acts::List,
ActiveRecord::Acts::Tree, ActiveRecord::Reflection,
ActiveRecord::Transactions, ActiveRecord::Aggregations,
ActiveRecord::Associations, ActiveRecord::Timestamp,
ActiveRecord::Observing, ActiveRecord::Callbacks,
ActiveRecord::Locking::Pessimistic,
ActiveRecord::Locking::Optimistic, ActiveRecord::Validations,
Reloadable::Deprecated, Object, PP::ObjectMixin, Base64::Deprecated,
Base64, Kernel]
…but an Array says:
Array.ancestors
=> [Array, ActiveSupport::CoreExtensions::Array::Grouping,
ActiveSupport::CoreExtensions::Array::Conversions, Enumerable,
Object, PP::ObjectMixin, Base64::Deprecated, Base64, Kernel]
And in a plain irb session:
irb(main):001:0> Array.ancestors
=> [Array, Enumerable, Object, Kernel]
I’m not sure whether the delete with block syntax you gave will work
on the “Array” (but I think that it does, try it in a safe
environment), but there is a delete method of the association that
takes a list of associated objects to be deleted and if they are in
a :dependent => :destroy relationship, the database record will be
removed, too.
-Rob