Pass an array to a new instance of a class

ruby-talk
#1

I am having trouble passing values to an array of a new instance of the
class Item that I have created. The following codse does not fille the
flags array with the value 'container'.

class Item
  attr_accessor :inum, :name, :description, :slot, :flags, :items

  def initialize( inum, name, description, slot, flags, items )
    @inum = inum
    @name = name
    @description = description
    @slot = slot
    @flags = []
    @items = []
  end

  def is_container
    return true if flags.include?(container)
  end
end

Item.new("0007", "crate", "A large crate.\r\n", ":none", "container",
"")

However when I use the code below, I am able to add the value
'container' to the flags array.

$rooms[("0001")].item("crate").flags << "container"

My question is, how do I modify the first bit of code to allow passing
values to the array of the new instance of the class Item?

···

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Posted via http://www.ruby-forum.com/.

#2

If I'm understanding right, the modifications I made to your code below
should do what you want

···

On Mon, Aug 30, 2010 at 9:21 AM, Jonathan Allen < jonathan.allen@insightbb.com> wrote:

I am having trouble passing values to an array of a new instance of the
class Item that I have created. The following codse does not fille the
flags array with the value 'container'.

class Item
attr_accessor :inum, :name, :description, :slot, :flags, :items

def initialize( inum, name, description, slot, flags, items )
   @inum = inum
   @name = name
   @description = description
   @slot = slot
   @flags = flags
   @items = items
end

def is_container
   return true if flags.include?(container)
end
end

Item.new("0007", "crate", "A large crate.\r\n", ":none", ["container"],
[])

However when I use the code below, I am able to add the value
'container' to the flags array.

$rooms[("0001")].item("crate").flags << "container"

My question is, how do I modify the first bit of code to allow passing
values to the array of the new instance of the class Item?
--
Posted via http://www.ruby-forum.com/.

#3

I am having trouble passing values to an array of a new instance of the
class Item that I have created. The following codse does not fille the
flags array with the value 'container'.

class Item
attr_accessor :inum, :name, :description, :slot, :flags, :items

def initialize( inum, name, description, slot, flags, items )
@inum = inum
@name = name
@description = description
@slot = slot
@flags = []
@items = []

You could do

@items = items.dup

i.e. copy an array passed via parameter "items". If you want to
explicitly create an array you can do

@items = [].concat items

If you do not always pass an Array you can do

@items = []
case items
when String
  @items << items
when Array
  @items.concat items
when Enumerable
  @items.concat items.to_a
else
  raise ArgumentError, "Dunno what to do with %p" % items
end

end

def is_container
return true if flags.include?(container)
end

You can simply do

def is_container?
  flags.include? container
end

end

Item.new("0007", "crate", "A large crate.\r\n", ":none", "container",
"")

However when I use the code below, I am able to add the value
'container' to the flags array.

$rooms[("0001")].item("crate").flags << "container"

My question is, how do I modify the first bit of code to allow passing
values to the array of the new instance of the class Item?

Hope the suggestions help.

Kind regards

robert

···

2010/8/30 Jonathan Allen <jonathan.allen@insightbb.com>:

--
remember.guy do |as, often| as.you_can - without end
http://blog.rubybestpractices.com/

#4

Apart from all the other suggestions, you should change the container
above to "container".

Jesus.

···

On Mon, Aug 30, 2010 at 3:21 PM, Jonathan Allen <jonathan.allen@insightbb.com> wrote:

def is_container
return true if flags.include?(container)
end
end

#5

Robert Klemme wrote:

If you do not always pass an Array you can do

@items = []
  @items << items

Thanks Robert. I didn't think about pushing the items into the array
from within the actual code for the class Item itself.

This worked just the way I was hoping. Thanks again!

···

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Posted via http://www.ruby-forum.com/.

#6

Note though that the code above only appends a single Array to the Array - it does not "push items into the array"! For that you need #concat as I have shown.

Kind regards

  robert

···

On 08/30/2010 04:56 PM, Jonathan Allen wrote:

Robert Klemme wrote:

If you do not always pass an Array you can do

@items = []
   @items<< items

Thanks Robert. I didn't think about pushing the items into the array
from within the actual code for the class Item itself.

This worked just the way I was hoping. Thanks again!

--
remember.guy do |as, often| as.you_can - without end
http://blog.rubybestpractices.com/