thr3ads.net - Rails - [Rails] Trouble with composed

If this information is useful, please help other people find it:
Share via:

Pat Maddox

2006-Mar-19 06:04 UTC

[Rails] Trouble with composed_of

I''m trying to use composed_of within my model.  I have a field in my
database named ''card1'', which is simply a string.  I have this
in my
model

class Player < ActiveRecord::Base
  composed_of :card1, :class_name => ''Card''
end

class Card
  attr_reader :value, :suit

  def initialize(s)
    @value = s[0].chr
    @suit = s[1].chr
  end
end

The accessor method works fine..in my fixture I have a Player created
with card1: As, and I can do
players(:first).card1.suit  #  => ''s''

But I can''t assign it:
players(:first).card = nil

Causes
NoMethodError: You have a nil object when you didn''t expect it!
The error occured while evaluating nil.card1
    (eval):3:in `card1=''
    test/unit/player_test.rb:51:in `test_validate_cards''

There is no validation for card1 in the Player class.  For some reason
I simply can''t assign card1.  What am I doing wrong?

Pat

Tom Mornini

2006-Mar-19 07:18 UTC

head link

[Rails] Trouble with composed_of

On Mar 18, 2006, at 10:04 PM, Pat Maddox wrote:
> I''m trying to use composed_of within my model.  I have a field in
my
> database named ''card1'', which is simply a string.  I have
this in my
> model
>
> class Player < ActiveRecord::Base
>   composed_of :card1, :class_name => ''Card''
> end
>
> class Card
>   attr_reader :value, :suit
>
>   def initialize(s)
>     @value = s[0].chr
>     @suit = s[1].chr
>   end
> end
>
> The accessor method works fine..in my fixture I have a Player created
> with card1: As, and I can do
> players(:first).card1.suit  #  => ''s''
>
> But I can''t assign it:
> players(:first).card = nil
I think that should be:

players(:first).card1 = nil

I''m sort of guessing that''s an email typo, though.

I wouldn''t be surprised if composed_of assignment
expects a composed_of object on assignment, i.e.
it wants to assign a Card object, not a nil object.

-- 
-- Tom Mornini

Pat Maddox

2006-Mar-19 10:49 UTC

head link

[Rails] Trouble with composed_of

On 3/19/06, Tom Mornini <tmornini@infomania.com>
wrote:> On Mar 18, 2006, at 10:04 PM, Pat Maddox wrote:
>
> > I''m trying to use composed_of within my model.  I have a
field in my
> > database named ''card1'', which is simply a string.  I
have this in my
> > model
> >
> > class Player < ActiveRecord::Base
> >   composed_of :card1, :class_name => ''Card''
> > end
> >
> > class Card
> >   attr_reader :value, :suit
> >
> >   def initialize(s)
> >     @value = s[0].chr
> >     @suit = s[1].chr
> >   end
> > end
> >
> > The accessor method works fine..in my fixture I have a Player created
> > with card1: As, and I can do
> > players(:first).card1.suit  #  => ''s''
> >
> > But I can''t assign it:
> > players(:first).card = nil
>
> I think that should be:
>
> players(:first).card1 = nil
>
> I''m sort of guessing that''s an email typo, though.
>
> I wouldn''t be surprised if composed_of assignment
> expects a composed_of object on assignment, i.e.
> it wants to assign a Card object, not a nil object.
>
> --
> -- Tom Mornini
>
> _______________________________________________
> Rails mailing list
> Rails@lists.rubyonrails.org
> http://lists.rubyonrails.org/mailman/listinfo/rails
>
Yeah, that''s just an email typo.  Anyway, setting it to a Card object
isn''t any better..
players(:first).card1 = Card.new ''Jd''

results in
  1) Error:
test_validate_cards(PlayerTest):
NoMethodError: undefined method `card1'' for #<Card:0x227263c
@suit="d", @value="J">
    (eval):3:in `card1=''
    test/unit/player_test.rb:51:in `test_validate_cards''

It''s obviously parsing the suit and rank fine..I don''t
understand what
the problem is.

Pat

Pat Maddox

2006-Mar-19 16:27 UTC

head link

[Rails] Trouble with composed_of

On 3/19/06, Pat Maddox <pergesu@gmail.com> wrote:> On 3/19/06, Tom Mornini <tmornini@infomania.com> wrote:
> > On Mar 18, 2006, at 10:04 PM, Pat Maddox wrote:
> >
> > > I''m trying to use composed_of within my model.  I have a
field in my
> > > database named ''card1'', which is simply a
string.  I have this in my
> > > model
> > >
> > > class Player < ActiveRecord::Base
> > >   composed_of :card1, :class_name => ''Card''
> > > end
> > >
> > > class Card
> > >   attr_reader :value, :suit
> > >
> > >   def initialize(s)
> > >     @value = s[0].chr
> > >     @suit = s[1].chr
> > >   end
> > > end
> > >
> > > The accessor method works fine..in my fixture I have a Player
created
> > > with card1: As, and I can do
> > > players(:first).card1.suit  #  => ''s''
> > >
> > > But I can''t assign it:
> > > players(:first).card = nil
> >
> > I think that should be:
> >
> > players(:first).card1 = nil
> >
> > I''m sort of guessing that''s an email typo, though.
> >
> > I wouldn''t be surprised if composed_of assignment
> > expects a composed_of object on assignment, i.e.
> > it wants to assign a Card object, not a nil object.
> >
> > --
> > -- Tom Mornini
> >
> > _______________________________________________
> > Rails mailing list
> > Rails@lists.rubyonrails.org
> > http://lists.rubyonrails.org/mailman/listinfo/rails
> >
>
> Yeah, that''s just an email typo.  Anyway, setting it to a Card
object
> isn''t any better..
> players(:first).card1 = Card.new ''Jd''
>
> results in
>   1) Error:
> test_validate_cards(PlayerTest):
> NoMethodError: undefined method `card1'' for #<Card:0x227263c
> @suit="d", @value="J">
>     (eval):3:in `card1=''
>     test/unit/player_test.rb:51:in `test_validate_cards''
>
> It''s obviously parsing the suit and rank fine..I don''t
understand what
> the problem is.
>
> Pat
>
I''ve kind of gotten around it..I made another attribute in the Card
class named create_str, and did the mapping as
composed_of :card1, :class_name => ''Card'', :mapping =>
%w(card1 create_str)

The Card class looks like
class Card
  attr_reader :suit, :rank, :create_str

  def to_s
    "#{@rank}#{@suit}"
  end

  def initialize(create_str)
    @create_str = create_str

    @rank = create_str[0].chr
    @suit = create_str[1].chr
  end
end

I still can''t set card1 to nil though.  I want to be able to make it
nil though, so I''m not really sure what to do.

composed_of looked like it''s what I needed, but I''m basically
unable
to figure it out..

Pat

Pat Maddox

2006-Mar-19 16:47 UTC

head link

[Rails] Trouble with composed_of

On 3/19/06, Pat Maddox <pergesu@gmail.com> wrote:> On 3/19/06, Pat Maddox <pergesu@gmail.com> wrote:
> > On 3/19/06, Tom Mornini <tmornini@infomania.com> wrote:
> > > On Mar 18, 2006, at 10:04 PM, Pat Maddox wrote:
> > >
> > > > I''m trying to use composed_of within my model.  I
have a field in my
> > > > database named ''card1'', which is simply a
string.  I have this in my
> > > > model
> > > >
> > > > class Player < ActiveRecord::Base
> > > >   composed_of :card1, :class_name =>
''Card''
> > > > end
> > > >
> > > > class Card
> > > >   attr_reader :value, :suit
> > > >
> > > >   def initialize(s)
> > > >     @value = s[0].chr
> > > >     @suit = s[1].chr
> > > >   end
> > > > end
> > > >
> > > > The accessor method works fine..in my fixture I have a
Player created
> > > > with card1: As, and I can do
> > > > players(:first).card1.suit  #  => ''s''
> > > >
> > > > But I can''t assign it:
> > > > players(:first).card = nil
> > >
> > > I think that should be:
> > >
> > > players(:first).card1 = nil
> > >
> > > I''m sort of guessing that''s an email typo,
though.
> > >
> > > I wouldn''t be surprised if composed_of assignment
> > > expects a composed_of object on assignment, i.e.
> > > it wants to assign a Card object, not a nil object.
> > >
> > > --
> > > -- Tom Mornini
> > >
> > > _______________________________________________
> > > Rails mailing list
> > > Rails@lists.rubyonrails.org
> > > http://lists.rubyonrails.org/mailman/listinfo/rails
> > >
> >
> > Yeah, that''s just an email typo.  Anyway, setting it to a
Card object
> > isn''t any better..
> > players(:first).card1 = Card.new ''Jd''
> >
> > results in
> >   1) Error:
> > test_validate_cards(PlayerTest):
> > NoMethodError: undefined method `card1'' for
#<Card:0x227263c
> > @suit="d", @value="J">
> >     (eval):3:in `card1=''
> >     test/unit/player_test.rb:51:in `test_validate_cards''
> >
> > It''s obviously parsing the suit and rank fine..I
don''t understand what
> > the problem is.
> >
> > Pat
> >
>
> I''ve kind of gotten around it..I made another attribute in the
Card
> class named create_str, and did the mapping as
> composed_of :card1, :class_name => ''Card'', :mapping
=> %w(card1 create_str)
>
> The Card class looks like
> class Card
>   attr_reader :suit, :rank, :create_str
>
>   def to_s
>     "#{@rank}#{@suit}"
>   end
>
>   def initialize(create_str)
>     @create_str = create_str
>
>     @rank = create_str[0].chr
>     @suit = create_str[1].chr
>   end
> end
>
> I still can''t set card1 to nil though.  I want to be able to make
it
> nil though, so I''m not really sure what to do.
>
> composed_of looked like it''s what I needed, but I''m
basically unable
> to figure it out..
>
> Pat
>
Well here''s my solution.  It''s kind of ugly and it bugs me
that it''s
so un-Railsy..but I don''t know of a better way.  I''d
appreciate input
from anyone else.

Pat


  def card1
    if self[:card1].nil? || self[:card1] == ''''
      nil
    else
      @card1_card ||= Card.new self[:card1]
    end
  end

  def card1=(c)
    @card1_card = c
    self[:card1] = "#{c}"
  end

  def card2
    if self[:card2].nil? || self[:card2] == ''''
      nil
    else
      @card2_card ||= Card.new self[:card2]
    end
  end

  def card2=(c)
    @card2_card = c
    self[:card2] = "#{c}"
  end

Seemingly Similar Threads

Search for more seemingly similar threads

Rails - Mar 2006 - Trouble with composed_of

[Rails] Trouble with composed_of

[Rails] Trouble with composed_of

[Rails] Trouble with composed_of

[Rails] Trouble with composed_of

[Rails] Trouble with composed_of

Seemingly Similar Threads