pname and version are not (yet) mandatory parameters. That allows you to have an almost empty derivation name. I'm not sure what's preferable at this moment, not having to write name = "${pname}-${version};, or risking not having a name. I'll guess it will be rare for someone to forget passing in a (p)name.

Some more clarification. I very much like this change and want this to happen as well, but I think we need to be sure whether this is the right direction. That is, perhaps we should fill in pname and version as much as possible. When most Python derivations have those attributes, we could then make this change, but at the same time also make pname and version mandatory. What do you think?

Specifying neither name nor pname and version results in the evaluation error. Please try it to see if the error is clear enough.

By the way, do you want to replace the usage of fetchurl with fetchPypi? If so, why?

By the way, do you want to replace the usage of fetchurl with fetchPypi? If so, why?

To easily fetch another version. See e.g. a3e5240#diff-9a467ecbd5ed7def480033cf9289509aR9

Tested it. Great!

Unfortunately it doesn't work as I hoped it would.

Building

foo.overrideAttrs (oldAttrs: {
  version = "1.2";
})

will give a version of foo that still has the old version in its name.

@FRidh You have to use overridePythonAttrs.

Ohh doh, how did I miss that. Thanks!