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Python

Posted by Simon Amz
Simon Amz
4,606 Points

custom validators

Hi,

In the code below, why the method 'must_be_empty' is outside the class. Being outside, it can be called anytime, anywhere?

def must_be_empty(value):
    if value:
        raise forms.ValidationError('is not empty')


class SuggestionForm(forms.Form):
    name = forms.CharField()
    email = forms.EmailField()
    suggestion = forms.CharField(widget=forms.Textarea)
    honeypot = forms.CharField(required=False,
                               widget=forms.HiddenInput,
                               label="Leave empty",
                               validators=[must_be_empty])

Besides, the method takes one argument 'value'. How could it be called by the validator without passing a parameter : 'validators=[must_be_empty]'

Thanks for your help

2 Answers

rshap
rshap
12,433 Points
rshap
rshap
12,433 Points

Here the the "must_be_empty()" function is global (as you said, not in the class) because of the "charfield", which takes in an array (validators) of functions that aren't part of a specific class. From what I understand form this course, the "charfield" element takes the validators array and just uses each item in it as a function with the value argument as the input in this field (in the html form).

Simon Amz
Simon Amz
4,606 Points
Simon Amz
Simon Amz
4,606 Points

thanks for the response