[Python-Dev] PEP 3101 implementation vs. documentation (original) (raw)

Greg Ewing greg.ewing at canterbury.ac.nz
Tue Jun 14 02:36:16 CEST 2011

Ben Wolfson wrote:

If by "item selector" you mean (using the names from the grammar in the docs) the elementindex, I don't see why this should be the case; dictionaries can contain non-identified keys, after all.

Of course they can, but that's not the point. The point is that putting arbitrary strings between [...] in a format spec without any form of quoting or requirement for bracket matching leads to something that's too confusing for humans to read.

IMO the spec should be designed so that the format string can be parsed using the same lexical analysis rules as Python code. That means anything that is meant to "hang together" as a single unit, such as an item selector, needs to look like a single Python token, e.g. an integer or identifier.

I realise this is probably more restrictive than the PEP suggests, but I think it would be better that way all round.

-- Greg

More information about the Python-Dev mailing list