lint for more unstable functions:

[llogiq]

iter.sum(), iter.product() – the former is usually equal to .fold(0, |acc, &i| acc + i), whereas the latter is equal to .fold(1, |prod, &i| prod * i). Need to check types, though.

[Manishearth]

Perhaps we should have a third lint group for stability lints?

[llogiq]

Makes sense.

[mcarton]

These methods have been stabilized in 1.11.0.