Try this:
class Product < ActiveRecord::Base
validates_format_of :hs_class_code, :with =>
/\A(\d{6}|\d{8}|\d{10})?\Z/
before_validation :clean_tariff_code
protected
def clean_tariff_code
self.hs_class_code.gsub!(".","") unless self.hs_class_code.nil?
end
It makes it more clear if you name the method. Also, it is a good idea to use self. to be sure that what are intended to be accessor method calls are not interpreted as local variables.
Another problem was the use of tr which returns nil if no substitution is made. The was your initial method was written, if hs_class_code did not contain the "." character, the result would be to call strip on nil.
Hope this helps
-Bill
James Byrne wrote:
Well, I am not sure about :with on before_validation as I don’t see it
in the docs or examples anywhere, but I’m not saying it won’t work, I
just don’t know. What I can do is show you how I do it and others may
chime in with alternatives / better solutions if some exist. First,
what I think you are asking is how to generically call your clean
method by passing in the attribute and the regex to use. Here are two
ways, one more verbose than the other, but it’s more self documenting.
`before_validation :delouse_hs_class_code
before_validation :delouse_another_one
protected
def delouse_another_one
delouse(:another_one,/\"/)
end
def delouse_hs_class_code
delouse(:hs_class_code,/\./)
end
def delouse(attr,regex)
`
`self.send(attr).gsub!(regex,"") unless self.send(attr).nil?`
end
Or you could use Proc’s
before_validation ``Proc.new{|o| o.delouse(:hs_class_code,/\./)}
`before_validation Proc.new{|o| o.delouse(:another_one,/"/)}
``
protected
``
def delouse(attr,regex)
`
`self.send(attr).gsub!(regex,"") unless self.send(attr).nil?`
end
`
`
This should get you going in the right direction. This is just a mock
up that I didn’t test exactly and this was also written before my first
cup of coffee 
HTH,
-Bill
James Byrne wrote:
As for the regex, I agree, always use what you want to allow rather
than attempting to guess everything you need to take out. In the
examples, I was just using what you had in the original method. As far
as passing options, you will need to use one of the 2 methods I
presented, both of which will allow multiple arguments.
-Bill
James Byrne wrote:
