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Diffstat (limited to 'solutions/quizzes/quiz3.rs')
| -rw-r--r-- | solutions/quizzes/quiz3.rs | 70 |
1 files changed, 69 insertions, 1 deletions
diff --git a/solutions/quizzes/quiz3.rs b/solutions/quizzes/quiz3.rs index 4e18198..e3413fd 100644 --- a/solutions/quizzes/quiz3.rs +++ b/solutions/quizzes/quiz3.rs @@ -1 +1,69 @@ -// Solutions will be available before the stable release. Thank you for testing the beta version 🥰 +// This quiz tests: +// - Generics +// - Traits +// +// An imaginary magical school has a new report card generation system written +// in Rust! Currently, the system only supports creating report cards where the +// student's grade is represented numerically (e.g. 1.0 -> 5.5). However, the +// school also issues alphabetical grades (A+ -> F-) and needs to be able to +// print both types of report card! +// +// Make the necessary code changes in the struct `ReportCard` and the impl +// block to support alphabetical report cards in addition to numerical ones. + +use std::fmt::Display; + +// Make the struct generic over `T`. +struct ReportCard<T> { + // ^^^ + grade: T, + // ^ + student_name: String, + student_age: u8, +} + +// To be able to print the grade, it has to implement the `Display` trait. +impl<T: Display> ReportCard<T> { + // ^^^^^^^ require that `T` implements `Display`. + fn print(&self) -> String { + format!( + "{} ({}) - achieved a grade of {}", + &self.student_name, &self.student_age, &self.grade, + ) + } +} + +fn main() { + // You can optionally experiment here. +} + +#[cfg(test)] +mod tests { + use super::*; + + #[test] + fn generate_numeric_report_card() { + let report_card = ReportCard { + grade: 2.1, + student_name: "Tom Wriggle".to_string(), + student_age: 12, + }; + assert_eq!( + report_card.print(), + "Tom Wriggle (12) - achieved a grade of 2.1", + ); + } + + #[test] + fn generate_alphabetic_report_card() { + let report_card = ReportCard { + grade: "A+", + student_name: "Gary Plotter".to_string(), + student_age: 11, + }; + assert_eq!( + report_card.print(), + "Gary Plotter (11) - achieved a grade of A+", + ); + } +} |
