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Hara Gopal K
Courses Plus Student 10,027 Pointscustom validators
in the given examples (name_exists, email_exists) how do the arguments form and field get passed to the functions?
- how does the variable "form" is actually referred the the Form class (we haven't created any instance of it yet..)
- is "field" a key word here?
1 Answer
Kenneth Love
Treehouse Guest TeacherHow the validators get called is separate from how we attach them to fields. Behind the scenes, there's a method that, effectively, is called on an existing Form instance. It'd do something like:
for validator in field.validators:
validator(form, field)
(hopefully that's obviously fake code)
We don't care about how that works when we're writing validators. We're concerned only with how to create a validator and get the correct validation.