As someone involved in the packaging side of this, I think while we'd eventually appreciate a TOML parser in the standard library, I agree with Victor that there's no rush, for two reasons:

1. setuptools and pip have a decent number of dependencies that we vendor anyway, so vendoring one more is not a big deal.
2. We will be supporting older versions of Python for some time to come, so we'd need to vendor a TOML-parser backport for several years before we could actually use the one in the standard library.

I think if a 1.0 version of the spec is going to be forthcoming (not clear from the issue requesting it: ), then it's worth waiting at least a bit longer for it.

I also think it's probably worth asking the current maintainers of TOML-parsing libraries if they think it's time to adopt/adapt one of their libraries for use in the standard library. They probably have a better perspective on the stability and maturity of their codebases.


On 5/15/19 8:39 AM, Victor Stinner wrote:
H Bastian,

IMHO we should wait until the format reach version 1.0, since the
stdlib has a slow release cycle (one release every 18 months). Too
slow for a "fast moving" standard.

In the meanwhile, I'm sure setuptools and pip will manage to install a
toml parser/generator for their needs, as they already do :-)


Le mer. 15 mai 2019 à 12:50, Bastian Venthur <> a écrit :
On 15.05.19 11:33, Antoine Pitrou wrote:
How stable is the TOML format?  Is it bound to change significantly in
the coming years?

If the format is stable enough, then I think it's a good idea.

The last update to the spec [1] was 10 months ago and added a few
features. The version before that was stable for more than 3 years. It
is also worth noting that he writes about the current version [2]:

"As of version 0.5.0, TOML should be considered extremely stable. The
goal is for version 1.0.0 to be backwards compatible (as much as humanly
possible) with version 0.5.0. All implementations are strongly
encouraged to become 0.5.0 compatible so that the transition to 1.0.0
will be simple when that happens."

That is of course no guarantee, but maybe the best we can hope for.




Dr. Bastian Venthur                        
Debian Developer                                 venthur at debian org

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