[chisleu]

Descriptive errors that match the business logic are ideal in many cases. Clearly, one shouldn't don't divulge "secret" validators.

More on the topic, I'm really happy to see this coming in so far ahead of 2.0. I want to get ready for 2.0 because of the gains I hope to see in idiomatic go in 2.0.

[SamWhited]

This is the general strategy when developing "2.0": do as much as possible in a backwards compatible way, and if we never need to make a breaking change, never call a release 2.0. The new features process that was introduced recently may result in a 2.0 release, or it may result in 1.999, so you will continue to see new features in each release for a while regardless of what the release is called.