Confusing error when attempting to install rust-docs component

[silverjam]

Ran the command curl https://sh.rustup.rs -sSf | sh to install rustup, then rustup component add rust-src which worked, then rustup component add rust-docs which fails with the following error:

error: component 'rust-docs' for target 'x86_64-apple-darwin' is required for toolchain 'stable-x86_64-apple-darwin' and cannot be re-added

Which is not google-able and doesn't seem (to me) to provide any clues on how to resolve the issue... any hints?

[Diggsey]

It means the documentation is already installed (it's a required component).

[silverjam]

Ok, would suggest re-wording the error... was following instructions here: http://asquera.de/blog/2017-03-03/setting-up-a-rust-devenv/ -- which seems to assume that it's not a required component.

[silverjam]

Suggest error: component 'rust-docs' is already added for target 'x86_64-apple-darwin' because it is required for toolchain 'stable-x86_64-apple-darwin' and cannot be re-added, type blah blah to see the component