Rails - May 2005 - undefined method `>' for nil:NilClass

I''m following the Depot tutorial in the Rails book, and have just hit a
wall.

As instructed by the tutorial, I added the following code to the Product model:

	protected
	def validate
		errors.add(:price, "should be positive") unless price > 0.0
	end

When I attempt to add a new product, I''m getting an error:

undefined method `>'' for nil:NilClass
/app/models/product.rb:11:in `validate''
app/controllers/admin_controller.rb:21:in `create''
./script/server:48

(This is on page 60 of the book).

The only thing I did differently from the book is use Sqlite3 instead
of MySQL. Everything was working until that ''errors.add'' line.

I know there''s a place for bugs about the book (if this even is one)
but I figured lots of people on this mailing list will be following
the book, so it''d be good to have an answer here too.

Thanks,
Ben

Solution:

errors.add(:price, "should be positive") unless price.to_f > 0.0

I guess because Sqlite doesn''t enforce data types everything comes
across as a string.

Ben

On 5/27/05, Ben Myles <ben.myles-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
wrote:
> I''m following the Depot tutorial in the Rails book, and have just
hit a wall.
> 
> As instructed by the tutorial, I added the following code to the Product
model:
> 
>         protected
>         def validate
>                 errors.add(:price, "should be positive") unless
price > 0.0
>         end
> 
> When I attempt to add a new product, I''m getting an error:
> 
> undefined method `>'' for nil:NilClass
> /app/models/product.rb:11:in `validate''
> app/controllers/admin_controller.rb:21:in `create''
> ./script/server:48
> 
> (This is on page 60 of the book).
> 
> The only thing I did differently from the book is use Sqlite3 instead
> of MySQL. Everything was working until that ''errors.add''
line.
> 
> I know there''s a place for bugs about the book (if this even is
one)
> but I figured lots of people on this mailing list will be following
> the book, so it''d be good to have an answer here too.
> 
> Thanks,
> Ben
>

That''s odd; your original error was complaining about price being nil,
no?

On 5/27/05, Ben Myles <ben.myles-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
wrote:
> Solution:
> 
> errors.add(:price, "should be positive") unless price.to_f >
0.0
> 
> I guess because Sqlite doesn''t enforce data types everything comes
> across as a string.
> 
> Ben
> 
> On 5/27/05, Ben Myles
<ben.myles-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
> > I''m following the Depot tutorial in the Rails book, and have
just hit a wall.
> >
> > As instructed by the tutorial, I added the following code to the
Product model:
> >
> >         protected
> >         def validate
> >                 errors.add(:price, "should be positive")
unless price > 0.0
> >         end
> >
> > When I attempt to add a new product, I''m getting an error:
> >
> > undefined method `>'' for nil:NilClass
> > /app/models/product.rb:11:in `validate''
> > app/controllers/admin_controller.rb:21:in `create''
> > ./script/server:48
> >
> > (This is on page 60 of the book).
> >
> > The only thing I did differently from the book is use Sqlite3 instead
> > of MySQL. Everything was working until that
''errors.add'' line.
> >
> > I know there''s a place for bugs about the book (if this even
is one)
> > but I figured lots of people on this mailing list will be following
> > the book, so it''d be good to have an answer here too.
> >
> > Thanks,
> > Ben
> >
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