I'm just relearning Rust after first using it in the pre-1.0 days. Predicting what kind of iterator I'm going to get in what circumstances has definitely been a

I'm just relearning Rust after first using it in the pre-1.0 days. Predicting what kind of iterator I'm going to get in what circumstances has definitely been a stumbling block for me. Sometimes it makes sense in retrospect (String::chars() must be producing copies not references, because it doesn't hold data as char internally, duh), but it is an area of the language where I frequently get unexpected compiler compiler errors.