Rust Generic Types and Methods | Programming Tutorials

Introduction

In this lab, we learn how to implement generic types and methods in Rust, allowing us to specify different type parameters when using the struct or calling the methods.

Note: If the lab does not specify a file name, you can use any file name you want. For example, you can use main.rs, compile and run it with rustc main.rs && ./main.

Skills Graph

%%%%{init: {'theme':'neutral'}}%%%% flowchart RL rust(("`Rust`")) -.-> rust/BasicConceptsGroup(["`Basic Concepts`"]) rust(("`Rust`")) -.-> rust/DataTypesGroup(["`Data Types`"]) rust(("`Rust`")) -.-> rust/FunctionsandClosuresGroup(["`Functions and Closures`"]) rust(("`Rust`")) -.-> rust/DataStructuresandEnumsGroup(["`Data Structures and Enums`"]) rust(("`Rust`")) -.-> rust/AdvancedTopicsGroup(["`Advanced Topics`"]) rust/BasicConceptsGroup -.-> rust/variable_declarations("`Variable Declarations`") rust/DataTypesGroup -.-> rust/floating_types("`Floating-point Types`") rust/DataTypesGroup -.-> rust/type_casting("`Type Conversion and Casting`") rust/FunctionsandClosuresGroup -.-> rust/function_syntax("`Function Syntax`") rust/FunctionsandClosuresGroup -.-> rust/expressions_statements("`Expressions and Statements`") rust/DataStructuresandEnumsGroup -.-> rust/method_syntax("`Method Syntax`") rust/AdvancedTopicsGroup -.-> rust/traits("`Traits`") rust/AdvancedTopicsGroup -.-> rust/operator_overloading("`Traits for Operator Overloading`") subgraph Lab Skills rust/variable_declarations -.-> lab-99346{{"`Implementing Generic Types in Rust`"}} rust/floating_types -.-> lab-99346{{"`Implementing Generic Types in Rust`"}} rust/type_casting -.-> lab-99346{{"`Implementing Generic Types in Rust`"}} rust/function_syntax -.-> lab-99346{{"`Implementing Generic Types in Rust`"}} rust/expressions_statements -.-> lab-99346{{"`Implementing Generic Types in Rust`"}} rust/method_syntax -.-> lab-99346{{"`Implementing Generic Types in Rust`"}} rust/traits -.-> lab-99346{{"`Implementing Generic Types in Rust`"}} rust/operator_overloading -.-> lab-99346{{"`Implementing Generic Types in Rust`"}} end

Implementation

Similar to functions, implementations require care to remain generic.

struct S; // Concrete type `S` struct GenericVal<T>(T); // Generic type `GenericVal` // impl of GenericVal where we explicitly specify type parameters: impl GenericVal<f32> {} // Specify `f32` impl GenericVal<S> {} // Specify `S` as defined above // `<T>` Must precede the type to remain generic impl<T> GenericVal<T> {}

struct Val { val: f64, } struct GenVal<T> { gen_val: T, } // impl of Val impl Val { fn value(&self) -> &f64 { &self.val } } // impl of GenVal for a generic type `T` impl<T> GenVal<T> { fn value(&self) -> &T { &self.gen_val } } fn main() { let x = Val { val: 3.0 }; let y = GenVal { gen_val: 3i32 }; println!("{}, {}", x.value(), y.value()); }

Implementing Generic Types in Rust

Introduction

Skills Graph

Implementation

Summary

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