django gotcha #1

form.py

In [1]: from django import forms

In [2]: class SampleForm(forms.Form):
   ...:     name = forms.CharField(max_length=10, initial='avil page')
   ...:     

In [3]: f = SampleForm()

In [4]: f.as_p()
Out[4]: u'<p>Name: <input maxlength="10" name="name" type="text" value="avil page" /></p>'

form2.py

In [11]: from django import forms

In [12]: class AdvancedForm(forms.Form):
   ....:    
   ....:    def __init__(self, *args, **kwargs):
   ....:        super().__init__(*args, **kwargs)
   ....:        self.fields['name'].initial =  'override'
   ....:    
   ....:        name=forms.CharField(max_length=10) 
   ....:    

In [13]: f2 = AdvancedForm()

In [14]: f2.as_p()
Out[14]: '<p>Name: <input maxlength="10" name="name" type="text" value="override" /></p>'

form3.py

In [11]: from django import forms

In [12]: class AdvancedForm(forms.Form):
   ....:    
   ....:    def __init__(self, *args, **kwargs):
   ....:        super().__init__(*args, **kwargs)
   ....:        self.fields['name'].initial = 'override'  # don't try this at home
   ....:    
   ....:        name=forms.CharField(max_length=10) 
   ....:    

In [19]: f3 = AdvancedForm(initial={'name': 'precedence'})

In [20]: f3.as_p()
Out[20]: '<p>Name: <input maxlength="10" name="name" type="text" value="precedence" /></p>'

form4.py

In [21]: from django import forms

In [22]: class AdvancedForm(forms.Form):
   ....:    
   ....:    def __init__(self, *args, **kwargs):
   ....:        super().__init__(*args, **kwargs)
   ....:        self.initial['name'] = 'override'  # aha!!!!                                                                                                   
   ....:     
   ....:        name=forms.CharField(max_length=10)
   ....:     

In [23]: f4 = AdvancedForm(initial={'name': 'precedence'})  
                                                                            
In [24]: f4.as_p()
Out[24]: '<p>Name: <input maxlength="10" name="name" type="text" value="override" /></p>'

form5.py

data = self.field.bound_data(
       self.data, 
       self.form.initial.get(self.name, self.field.initial)  # precedence matters!!!!
)