rust / intermediate
Snippet
Generic Traits with Where Clauses
Where clauses provide a cleaner way to express complex generic constraints compared to inline trait bounds. They allow multiple constraints on a single type parameter and become essential when dealing with several generic parameters or complex trait combinations.
snippet.rs
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use std::fmt::{Display, Debug};fn print_debug<T, U>(t: T, u: U) -> StringwhereT: Display + Debug,U: Clone + Into<String>,{format!("T: {:?}, U: {}", t, u.clone())}fn main() {println!("{}", print_debug(42, "hello"));}
Breakdown
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use std::fmt::{Display, Debug};
Import Display and Debug traits needed for the generic constraints
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fn print_debug<T, U>(t: T, u: U) -> String
Function with two generic type parameters T and U
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where T: Display + Debug,
T must implement both Display (for printing) and Debug (for {:?} formatting)
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U: Clone + Into<String>,
U must be cloneable and convertible into a String
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format!("T: {:?}, U: {}", t, u.clone())
Uses Debug formatting for t and clones u to satisfy the Into<String> constraint