vendor/rails/activerecord/lib/active_record/validations.rb
# Validates whether the value of the specified attribute is numeric by trying to convert it to
# a float with Kernel.Float (if <tt>only_integer</tt> is false) or applying it to the regular expression
# <tt>/\A[\+\-]?\d+\Z/</tt> (if <tt>only_integer</tt> is set to true).
#
#   class Person < ActiveRecord::Base
#     validates_numericality_of :value, :on => :create
#   end
#
# Configuration options:
# * <tt>:message</tt> - A custom error message (default is: "is not a number").
# * <tt>:on</tt> - Specifies when this validation is active (default is <tt>:save</tt>, other options <tt>:create</tt>, <tt>:update</tt>).
# * <tt>:only_integer</tt> - Specifies whether the value has to be an integer, e.g. an integral value (default is +false+).
# * <tt>:allow_nil</tt> - Skip validation if attribute is +nil+ (default is +false+). Notice that for fixnum and float columns empty strings are converted to +nil+.
# * <tt>:greater_than</tt> - Specifies the value must be greater than the supplied value.
# * <tt>:greater_than_or_equal_to</tt> - Specifies the value must be greater than or equal the supplied value.
# * <tt>:equal_to</tt> - Specifies the value must be equal to the supplied value.
# * <tt>:less_than</tt> - Specifies the value must be less than the supplied value.
# * <tt>:less_than_or_equal_to</tt> - Specifies the value must be less than or equal the supplied value.
# * <tt>:odd</tt> - Specifies the value must be an odd number.
# * <tt>:even</tt> - Specifies the value must be an even number.
# * <tt>:if</tt> - Specifies a method, proc or string to call to determine if the validation should
#   occur (e.g. <tt>:if => :allow_validation</tt>, or <tt>:if => Proc.new { |user| user.signup_step > 2 }</tt>).  The
#   method, proc or string should return or evaluate to a true or false value.
# * <tt>:unless</tt> - Specifies a method, proc or string to call to determine if the validation should
#   not occur (e.g. <tt>:unless => :skip_validation</tt>, or <tt>:unless => Proc.new { |user| user.signup_step <= 2 }</tt>).  The
#   method, proc or string should return or evaluate to a true or false value.




Configuration options:
:message - A custom error message (default is: "is not a number").
:on - Specifies when this validation is active (default is :save, other options :create, :update).
:only_integer - Specifies whether the value has to be an integer, e.g. an integral value (default is +false+).
:allow_nil - Skip validation if attribute is +nil+ (default is +false+). Notice that for fixnum and float columns empty strings are converted to +nil+.
:greater_than - Specifies the value must be greater than the supplied value.
:greater_than_or_equal_to - Specifies the value must be greater than or equal the supplied value.
:equal_to - Specifies the value must be equal to the supplied value.
:less_than - Specifies the value must be less than the supplied value.
:less_than_or_equal_to - Specifies the value must be less than or equal the supplied value.
:odd - Specifies the value must be an odd number.
:even - Specifies the value must be an even number.
:if - Specifies a method, proc or string to call to determine if the validation should
occur .  The
method, proc or string should return or evaluate to a true or false value.
:unless - Specifies a method, proc or string to call to determine if the validation should
not occur .  The
method, proc or string should return or evaluate to a true or false value.
Configuration options : : message - A custom error message ( default is : " is not a number " ) . : on - Specifies when this validation is active ( default is : save other options : create : update ) . : only_integer - Specifies whether the value has to be an integer e . g . an integral value ( default is + false + ) . : allow_nil - Skip validation if attribute is + nil + ( default is + false + ) . Notice that for fixnum and float columns empty strings are converted to + nil + . : greater_than - Specifies the value must be greater than the supplied value . : greater_than_or_equal_to - Specifies the value must be greater than or equal the supplied value . : equal_to - Specifies the value must be equal to the supplied value . : less_than - Specifies the value must be less than the supplied value . : less_than_or_equal_to - Specifies the value must be less than or equal the supplied value . : odd - Specifies the value must be an odd number . : even - Specifies the value must be an even number . : if - Specifies a method proc or string to call to determine if the validation should occur . The method proc or string should return or evaluate to a true or false value . : unless - Specifies a method proc or string to call to determine if the validation should not occur . The method proc or string should return or evaluate to a true or false value .
def validates_numericality_of(*attr_names)
        configuration = { :on => :save, :only_integer => false, :allow_nil => false }
        configuration.update(attr_names.extract_options!)
        numericality_options = ALL_NUMERICALITY_CHECKS.keys & configuration.keys
        (numericality_options - [ :odd, :even ]).each do |option|
          raise ArgumentError, ":#{option} must be a number" unless configuration[option].is_a?(Numeric)
        end
        validates_each(attr_names,configuration) do |record, attr_name, value|
          raw_value = record.send("#{attr_name}_before_type_cast") || value
          next if configuration[:allow_nil] and raw_value.nil?
          if configuration[:only_integer]
            unless raw_value.to_s =~ /\A[+-]?\d+\Z/
              record.errors.add(attr_name, :not_a_number, :value => raw_value, :default => configuration[:message])
              next
            end
            raw_value = raw_value.to_i
          else
            begin
              raw_value = Kernel.Float(raw_value)
            rescue ArgumentError, TypeError
              record.errors.add(attr_name, :not_a_number, :value => raw_value, :default => configuration[:message])
              next
            end
          end
          numericality_options.each do |option|
            case option
              when :odd, :even
                unless raw_value.to_i.method(ALL_NUMERICALITY_CHECKS[option])[]
                  record.errors.add(attr_name, option, :value => raw_value, :default => configuration[:message]) 
                end
              else
                record.errors.add(attr_name, option, :default => configuration[:message], :value => raw_value, :count => configuration[option]) unless raw_value.method(ALL_NUMERICALITY_CHECKS[option])[configuration[option]]
            end
          end
        end
      end
def validates_numericality_of ( * attr_names ) configuration = { :on => :save , :only_integer => false , :allow_nil => false } configuration . update ( attr_names . extract_options! ) numericality_options = ALL_NUMERICALITY_CHECKS . keys & configuration . keys ( numericality_options - [ :odd , :even ] ) . each do | option | raise ArgumentError , ":#{option} must be a number" unless configuration [ option ] . is_a? ( Numeric ) end validates_each ( attr_names , configuration ) do | record , attr_name , value | raw_value = record . send ( "#{attr_name}_before_type_cast" ) || value next if configuration [ :allow_nil ] and raw_value . nil? if configuration [ :only_integer ] unless raw_value . to_s =~ / \A [+-]? \d + \Z / record . errors . add ( attr_name , :not_a_number , :value => raw_value , :default => configuration [ :message ] ) next end raw_value = raw_value . to_i else begin raw_value = Kernel . Float ( raw_value ) rescue ArgumentError , TypeError record . errors . add ( attr_name , :not_a_number , :value => raw_value , :default => configuration [ :message ] ) next end end numericality_options . each do | option | case option when :odd , :even unless raw_value . to_i . method ( ALL_NUMERICALITY_CHECKS [ option ] ) [ ] record . errors . add ( attr_name , option , :value => raw_value , :default => configuration [ :message ] ) end else record . errors . add ( attr_name , option , :default => configuration [ :message ] , :value => raw_value , :count => configuration [ option ] ) unless raw_value . method ( ALL_NUMERICALITY_CHECKS [ option ] ) [ configuration [ option ] ] end end end end
Validates whether the value of the specified attribute is numeric by trying to convert it to
a float with Kernel.Float (if <tt>only_integer</tt> is false) or applying it to the regular expression
<tt>/\A[\+\-]?\d+\Z/</tt> (if <tt>only_integer</tt> is set to true).
Validates whether the value of the specified attribute is numeric by trying to convert it to a float with Kernel . Float ( if <tt > only_integer< / tt > is false ) or applying it to the regular expression <tt > / \ A [ \ + \ - ] ? \ d + \ Z / < / tt > ( if <tt > only_integer< / tt > is set to true ) .
attr_names