Creating formatted output using picture strings

[Peter Otten]

python at bdurham.com wrote:

> Does Python provide a way to format a string according to a
> 'picture' format?
> 
> For example, if I have a string '123456789' and want it formatted
> like '(123)-45-(678)[9]', is there a module or function that will
> allow me to do this or do I need to code this type of
> transformation myself?

A basic implementation without regular expressions:

>>> def picture(s, pic, placeholder="@"):
...     parts = pic.split(placeholder)
...     result = [None]*(len(parts)+len(s))
...     result[::2] = parts
...     result[1::2] = s
...     return "".join(result)
...
>>>
>>> picture("123456789", "(@@@)-@@-(@@@)[@]")
'(123)-45-(678)[9]'

Peter