format

f-strings and str.format()
- Exa: 0.4f, 0.2f
Each of one types, int or float, support different kind of formats for example
- int can be formatted as base 2 and base 16
- float can be formmated using fixed-point and % percentage
- strftime is to support datetime or dates in general
There is a mini-language for the formatters
- Avoid the same letter or codes for custom regarding string, int and float
  - You can use p for polar coordinates for example

def __format__(self, fmt_spec=''):
        components = (format(c, fmt_spec) for c in self)
        return '({}, {})'.format(*components)

 def __format__(self, fmt_spec=''):
        if fmt_spec.endswith('p'):
            fmt_spec = fmt_spec[:-1]
            coords = (abs(self), self.angle())
            outer_fmt = '<{}, {}>'
        else:
            coords = self
            outer_fmt = '({}, {})'
        components = (format(c, fmt_spec) for c in coords)
        return outer_fmt.format(*components)

>>> format(Vector2d(1, 1), 'p')
'<1.4142135623730951, 0.7853981633974483>'
>>> format(Vector2d(1, 1), '.3ep')
'<1.414e+00, 7.854e-01>'
>>> format(Vector2d(1, 1), '0.5fp')
'<1.41421, 0.78540>'

References

Ramalho, 2022, p370-374