way to create fstring inside a fstring

Question

is it possible to create a fstring inside a fstring?

what i am trying now is to create a dynamic function using eval.

my code is something like this

func_string = ''
for scenario in ['scene1', 'scene2']:
    for aa in ['int', 'ext']:
         func_string += f'''
             def function_{scenario}_{aa}(part):
                 print(f"this is {part}")
           '''


eval(func_string)
function_scene1_int('part1')

running this script will return: this is part1

And what should it return? It successfully replaced {part} with "part1" — Andrew Morozko, Jun 26 '18 at 10:03
i need to create 30 function on the fly, do you have any suggestion i can do this without code out all these functions explicitly — user466130, Jun 26 '18 at 10:07
It can work but is an anti-pattern. Dynamical creation of variables or functions is (almost) always a poor answer to a real problem. — Serge Ballesta, Jun 26 '18 at 10:23
Serge Ballesta, do you have better suggestion to create 30 callback functions as shown in the first example of https://dash.plot.ly/getting-started-part-2? — user466130, Jun 26 '18 at 10:33

joel · Accepted Answer · 2018-06-26T10:21:51.537

1

You can make a factory method like this ...

def factory(a, b):
    def g(c):
        print(f'this is {c}')
        return f'other stuff using {a}, {b} and {c}'  # if you want to
    return g

then use it like

>>> f = factory('scene1', 'int')
>>> msg = f('part1')
this is part1
>>> print(msg)
other stuff using scene1, int and part1

edited Jun 26 '18 at 10:21

answered Jun 26 '18 at 10:14

joel

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aha...i can smell the answer...:) – user466130 Jun 26 '18 at 10:21

way to create fstring inside a fstring

1 Answers1