# Validates\_numercality\_of with allow\_nil **URL:** \ **Category:** Rails\ **Created:** [June 19, 2011, 1:25pm UTC](https://www.ruby-forum.com/t/validates-numercality-of-with-allow-nil/208464 "2011-06-19T13:25:12Z")\ **Posts on this page:** 11\ **Page:** 1
**Author:** ![dubstep](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/cdc98d/32.png) [@dubstep](https://www.ruby-forum.com/u/dubstep)\ **Post date:** [June 19, 2011, 1:25pm UTC](https://www.ruby-forum.com/t/validates-numercality-of-with-allow-nil/208464/1 "2011-06-19T13:25:12Z")
In the model I have: validates :square\_meters\_public\_land, :barrier\_meters, :numericality =\> { :greater\_than\_or\_equal\_to =\> 0 }, :allow\_nil =\> true but if, in the field, on create, I don’t insert a value I have the error “field is not a number”. ---
**Author:** ![msan](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/m/3ab097/32.png) [@msan](https://www.ruby-forum.com/u/msan)\ **Post date:** [June 19, 2011, 1:40pm UTC](https://www.ruby-forum.com/t/validates-numercality-of-with-allow-nil/208464/2 "2011-06-19T13:40:38Z")
On 19 June 2011 12:23, Mauro [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > In the model I have: > > validates :square\_meters\_public\_land, :barrier\_meters, :numericality > =\> { :greater\_than\_or\_equal\_to =\> 0 }, :allow\_nil =\> true Depending on your Rails version… try: validates :square\_meters\_public\_land, :barrier\_meters, :numericality =\> { :greater\_than\_or\_equal\_to =\> 0 }, :if =\> Proc.new {|o| !o.square\_meters\_public\_land.blank?} or validates :square\_meters\_public\_land, :barrier\_meters, :numericality =\> { :greater\_than\_or\_equal\_to =\> 0 }, :if =\> :square\_meters\_public\_land ---
**Author:** ![msan](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/m/3ab097/32.png) [@msan](https://www.ruby-forum.com/u/msan)\ **Post date:** [June 19, 2011, 2:19pm UTC](https://www.ruby-forum.com/t/validates-numercality-of-with-allow-nil/208464/3 "2011-06-19T14:19:30Z")
On 19 June 2011 13:38, Michael P. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > On 19 June 2011 12:23, Mauro [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > > > In the model I have: > > > > validates :square\_meters\_public\_land, :barrier\_meters, :numericality > > =\> { :greater\_than\_or\_equal\_to =\> 0 }, :allow\_nil =\> true > > Depending on your Rails version… try: I’m using rails 3.0.9, sorry but I don’t undestand why I have to use the if clause. allow\_nil =\> doens’t work with validation\_numericality\_of? ---
**Author:** ![msan](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/m/3ab097/32.png) [@msan](https://www.ruby-forum.com/u/msan)\ **Post date:** [June 19, 2011, 2:28pm UTC](https://www.ruby-forum.com/t/validates-numercality-of-with-allow-nil/208464/4 "2011-06-19T14:28:08Z")
On 19 June 2011 13:18, Mauro [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > I’m using rails 3.0.9, sorry but I don’t undestand why I have to use > the if clause. > allow\_nil =\> doens’t work with validation\_numericality\_of? I didn’t say you “had to”, I suggested you try it… did you? Did it work?.. I doubt it anyway, as I had copied your code without checking it, and just added the “if” I’d copied from one of my models. I notice now that you’re not using “validates\_numericality\_of”, you’re using “validates” and seem to be trying to check two values - can’t say that’s an idiom I’m familiar with, but it may be valid (although I can’t see it in the docs: [http://ar.rubyonrails.org/classes/ActiveRecord/Validations/ClassMethods.html#M000091](http://ar.rubyonrails.org/classes/ActiveRecord/Validations/ClassMethods.html#M000091)) What about: validates\_numericality\_of :square\_meters\_public\_land, :greater\_than\_or\_equal\_to =\> 0, :allow\_nil =\> true validates\_numericality\_of :barrier\_meters, :greater\_than\_or\_equal\_to =\> 0, :allow\_nil =\> true ---
**Author:** ![msan](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/m/3ab097/32.png) [@msan](https://www.ruby-forum.com/u/msan)\ **Post date:** [June 19, 2011, 7:13pm UTC](https://www.ruby-forum.com/t/validates-numercality-of-with-allow-nil/208464/5 "2011-06-19T19:13:00Z")
On 19 June 2011 13:38, Michael P. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > =\> { :greater\_than\_or\_equal\_to =\> 0 }, :if =\> Proc.new {|o| > !o.square\_meters\_public\_land.blank?} > > or > > validates :square\_meters\_public\_land, :barrier\_meters, :numericality > =\> { :greater\_than\_or\_equal\_to =\> 0 }, :if =\> > :square\_meters\_public\_land Same problem, I don’t know how to insert nil values for the two fields. ---
**Author:** ![msan](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/m/3ab097/32.png) [@msan](https://www.ruby-forum.com/u/msan)\ **Post date:** [June 19, 2011, 7:05pm UTC](https://www.ruby-forum.com/t/validates-numercality-of-with-allow-nil/208464/6 "2011-06-19T19:05:36Z")
On 19 June 2011 14:26, Michael P. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > What about: > > validates\_numericality\_of :square\_meters\_public\_land, > :greater\_than\_or\_equal\_to =\> 0, :allow\_nil =\> true > validates\_numericality\_of :barrier\_meters, :greater\_than\_or\_equal\_to > =\> 0, :allow\_nil =\> true It’s just the same. ---
**Author:** ![msan](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/m/3ab097/32.png) [@msan](https://www.ruby-forum.com/u/msan)\ **Post date:** [June 19, 2011, 8:11pm UTC](https://www.ruby-forum.com/t/validates-numercality-of-with-allow-nil/208464/7 "2011-06-19T20:11:45Z")
On 19 June 2011 18:04, Mauro [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > > validates\_numericality\_of :barrier\_meters, :greater\_than\_or\_equal\_to > > =\> 0, :allow\_nil =\> true > > It’s just the same. Curious. Okay, so lastly, try: validates\_numericality\_of :square\_meters\_public\_land, :greater\_than\_or\_equal\_to =\> 0, :if =\> :square\_meters\_public\_land validates\_numericality\_of :barrier\_meters, :greater\_than\_or\_equal\_to =\> 0, :if =\> :barrier\_meters ---
**Author:** ![msan](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/m/3ab097/32.png) [@msan](https://www.ruby-forum.com/u/msan)\ **Post date:** [June 19, 2011, 7:48pm UTC](https://www.ruby-forum.com/t/validates-numercality-of-with-allow-nil/208464/8 "2011-06-19T19:48:16Z")
On Jun 19, 2011, at 7:23 AM, Mauro wrote: > In the model I have: > > validates :square\_meters\_public\_land, :barrier\_meters, :numericality > =\> { :greater\_than\_or\_equal\_to =\> 0 }, :allow\_nil =\> true > > but if, in the field, on create, I don’t insert a value I have the > error “field is not a number”. Include the :allow\_blank option if the fields are not required. I generally think about this in terms of “specifying a validation always includes :required; if that’s not what I want, I have to include :allow\_blank”. cheers, Bill ---
**Author:** ![msan](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/m/3ab097/32.png) [@msan](https://www.ruby-forum.com/u/msan)\ **Post date:** [June 19, 2011, 9:27pm UTC](https://www.ruby-forum.com/t/validates-numercality-of-with-allow-nil/208464/9 "2011-06-19T21:27:09Z")
On Jun 19, 2011, at 2:43 PM, Mauro wrote: > > > error “field is not a number”. > > > > Include the :allow\_blank option if the fields are not required. > > I generally think about this in terms of “specifying a validation always > > includes :required; if that’s not what I want, I have to include :allow\_blank”. > > That’s ok, they are numeric fields I thought that allow\_nil should be ok. I would have expected :allow\_nil to work, but apparently it’s giving problems? FWIW, I always tend to think in terms of :allow\_blank rather than :allow\_nil. Perhaps an artifact of my years in Smalltalk? If :allow\_nil isn’t working, as I gather from the posts that appeared before mine (after I posted, but long before mine showed up), have you tried :allow\_blank? Does that work better, worse, or no different? regards, Bill ---
**Author:** ![msan](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/m/3ab097/32.png) [@msan](https://www.ruby-forum.com/u/msan)\ **Post date:** [June 19, 2011, 8:44pm UTC](https://www.ruby-forum.com/t/validates-numercality-of-with-allow-nil/208464/10 "2011-06-19T20:44:31Z")
On 19 June 2011 13:43, Bill F. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > Include the :allow\_blank option if the fields are not required. > I generally think about this in terms of “specifying a validation always > includes :required; if that’s not what I want, I have to include :allow\_blank”. That’s ok, they are numeric fields I thought that allow\_nil should be ok. ---
**Author:** ![msan](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/m/3ab097/32.png) [@msan](https://www.ruby-forum.com/u/msan)\ **Post date:** [June 19, 2011, 11:21pm UTC](https://www.ruby-forum.com/t/validates-numercality-of-with-allow-nil/208464/11 "2011-06-19T23:21:28Z")
On 19 June 2011 21:26, Bill F. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > > > > =\> { :greater\_than\_or\_equal\_to =\> 0 }, :allow\_nil =\> true > > > > I would have expected :allow\_nil to work, but apparently it’s giving problems? > > > > FWIW, I always tend to think in terms of :allow\_blank rather than :allow\_nil. > > > > Perhaps an artifact of my years in Smalltalk? > > > > If :allow\_nil isn’t working, as I gather from the posts that appeared before > > > > mine (after I posted, but long before mine showed up), have you tried > > > > :allow\_blank? Does that work better, worse, or no different? allow\_blank works.