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tabs for indentation, spaces for alignment

And if you mix both every language that relies on indentation (Python e.g.) throws you a nice warning or even an error.

The only exception I can think for the 'use tabs' rule in languages without Lisp syntax is precisely Python.

Therefore, to me, your 'every language' reduces to a list of one.

Indentation is also significant in Haskell, for example.

If there was an automated tool that could apply that I would agree with you.