error[E0433]: failed to resolve: use of undeclared type `HashMap` --> $DIR/use_suggestion.rs:2:14 | LL | let x1 = HashMap::new(); | ^^^^^^^ use of undeclared type `HashMap` | help: consider importing this struct | LL | use std::collections::HashMap; | error[E0412]: cannot find type `HashMap` in this scope --> $DIR/use_suggestion.rs:5:13 | LL | let y1: HashMap; | ^^^^^^^ not found in this scope | help: consider importing this struct | LL | use std::collections::HashMap; | error[E0412]: cannot find type `GooMap` in this scope --> $DIR/use_suggestion.rs:6:13 | LL | let y2: GooMap; | ^^^^^^ not found in this scope error[E0433]: failed to resolve: use of undeclared type `GooMap` --> $DIR/use_suggestion.rs:3:14 | LL | let x2 = GooMap::new(); | ^^^^^^ use of undeclared type `GooMap` error: aborting due to 4 previous errors Some errors have detailed explanations: E0412, E0433. For more information about an error, try `rustc --explain E0412`.