Adding a type or catogory flag

[vbastos]

Hi Arthur,

Would you be open to adding a flag to the number to identify if they are a tax identifier for example or a bank identifier or just a number check? As well as an api to get a list of numbers that match a type?

[pokoli]

Here is a link to the discussing that originated this issue:

https://discuss.tryton.org/t/localisation-module-for-tax-identifier-australia/573/10

Our use case is to get a list of all the available tax identifiers using a code and a description of it.

So if a new tax identifier is added on the python-stdnum package it will be added to our list of available identifiers once the python-stdnum lib is updated.

[arthurdejong]

I like the idea of a classification mechanism in python-stdnum and a mechanism that allows one to find a list of validation modules based on certain criteria.
There is already a helper function available that has a limited implementation of that idea but a more generic solution would be nicer.
The funny thing with tax identifiers is that their use is quite different across countries. For example some countries use one number for all tax purposes while others have a different number for each type of tax.
The question really is, what kind of API would you like python-stdnum to provide?
Do you want to be able to get all number formats in a particular country that are related to taxes, various numbers across countries, do you want to have sub-types (e.g. a VAT number is a tax number but not all tax numbers are VAT numbers). After that the classification should be straightforward.