Advice on using define_method in ActiveRecord descendant

All,

I have five accessor methods in an AR descendant that are virtually the
same. I wanted to try and use define_method to auto-define all five
methods, but I can’t seem to get it to work.

Here are the methods:

def gross_receipts=(new_value)
write_attribute(:gross_receipts, new_value.to_s.gsub(/,/, ‘’))
end

def number_of_owners=(new_value)
write_attribute(:number_of_owners, new_value.to_s.gsub(/,/, ‘’))
end

def annual_employee_payroll=(new_value)
write_attribute(:annual_employee_payroll, new_value.to_s.gsub(/,/,
‘’))
end

def uninsured_subcontractors_contract_cost=(new_value)
write_attribute(:uninsured_subcontractors_contract_cost,
new_value.to_s.gsub(/,/, ‘’))
end

def insured_subcontractors_contract_cost=(new_value)
write_attribute(:insured_subcontractors_contract_cost,
new_value.to_s.gsub(/,/, ‘’))
end

and here is what I tried to do to auto-create them:

for attr in [ :gross_receipts, :number_of_owners,
:annual_employee_payroll, :uninsured_subcontractors_contract_cost,
:insured_subcontractors_contract_cost ] do
self.class_eval do
define_method("#{attr.to_s}=(new_value)") {
write_attribute(attr, new_value.to_s.gsub(/,/, ‘’))
}
end
end

The for loop is syntactically correct, but these methods do not exist if
I create a new instance of this object.

Is it because these methods don’t exist in the first place (they’re
auto-created by ActiveRecord anyway)?

What am I doing wrong?

Thanks,
Wes