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Comment by CrLf | Hacker News Reader

Having a choice on when to use the existing string formatting methods is a feature. I tend to use ‘%’ a lot for it’s compactness and f-strings most more rarely (admittedly there doesn’t seem to be much reason to use .format these days).

In general I don’t understand the need to hard-standardize code. Making subtle decisions depending on context is an important part of programming, please let humans decide and don’t use these types of tools in commit hooks...

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One case where .format comes in handy:

    your_dict = {
        "some": "awesome",
        "from": "out of",
        "dictionary": "mapping",
    }
    "insert {some} values {from} a {dictionary}".format(**your_dict)

That is a very neat trick indeed, I'll have to remember this one!

This can also be achieved using '%':

  your_dict = {
    "some": "awesome",
    "from": "out of",
    "dictionary": "mapping",
  }
  "insert %(some)s values %(from)s a %(dictionary)s" % your_dict

WRT .format, '%' is safer to use with untrusted (well, semi-trusted) format strings, whereas .format can lead to code injection (in more insidious ways than with f-strings).

You'd be better off using "...".format_map(your_dict). This case is exactly why it exists.

> Making subtle decisions depending on context is an important part of programming.

Yes, and so is deciding what context matters across a whole team or team-of-teams.

Which is usually an excuse to enforce the personal preferences of some. Programming is not an activity performed by robots (yet).

> an excuse

Whenever I see this word, I see a trust or communication problem.

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