[Python-Dev] Re: Delayed evaluation of f-strings?

June 24, 2021

      On Thu, 24 Jun 2021 at 17:37, Martin (gzlist) <gzlist@googlemail.com> wrote:
...
>>> d = dict(a=1)
    >>> f'{d["a"]}'
    '1'
    >>> str(DelayedFString('{d["a"]}'))
    Traceback (most recent call last):
      File "<stdin>", line 1, in <module>
      File "<stdin>", line 5, in __str__
    KeyError: '"a"'
And the other side of the attribute lookup:

    >>> d = dict(a=1)
    >>> str(DelayedFString('{d[a]}'))
    '1'
    >>> f'{d[a]}'
    Traceback (most recent call last):
      File "<stdin>", line 1, in <module>
    NameError: name 'a' is not defined

Yes, having three different ways of doing string interpolation (not
counting other things you can import, like string.Template) is a bit
confusing.

Martin