const functions: separate rule about users and rule about what is allowed in such functions by tshepang · Pull Request #2013 · rust-lang/reference (original) (raw)

There were two sections defining const functions, which was a little confusing to me and made it a little difficult to maintain them. This combines them so that there is only one section. It could have gone in either chapter, but I arbitrarily picked const-eval.

This removes items.fn.const.extern. The reference generally assumes that if something can be defined, it can be used unless explicitly restricted. This used to be a restriction, but it morphed over time as extern support was slowly added.

I noticed that const-eval.const-fn.type-restrictions is not clear to me and needs further work to explain the type restrictions.