methods: people might be using to_string() to make a copy; add a hint for that
methods: people might be using to_string() to make a copy; add a hint for that

aidancully/rust,graydon/rust,aidancully/rust,graydon/rust,graydon/rust,graydon/rust,aidancully/rust,aidancully/rust,aidancully/rust,graydon/rust,graydon/rust,aidancully/rust