Rust by Example: Variables

In Rust, variables provide explicit type information, aiding in type safety checks by the compiler. Here, we demonstrate variable mutability, reassignment, type inference, and explicit type declaration. Additionally, Rust allows variable shadowing, enabling the redeclaration of a variable with a different type.
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fn main() {

By default, variables are immutable

 
    let x = 5;
    println!("The value of x is: {}", x);

To make a variable mutable, use the mut keyword

 
    let mut y = 5;
    println!("The value of y is: {}", y);

Variables can be reassigned

 
    y = 6;
    println!("The value of y is: {}", y);

Types can be inferred

 
    let z = 5; // z: i32
    println!("The value of z is: {}", z);

Or types can be explicitly declared

 
    let a: i32 = 5;
    println!("The value of a is: {}", a);

Variables can be shadowed, the variable a is redeclared with a different type, and the value is reassigned.

 
    let a = "hello, world!";
    println!("The value of a is: {}", a);
}

$ rustc variables.rs
$ ./variables
The value of x is: 5
The value of y is: 5
The value of y is: 6
The value of z is: 5
The value of a is: 5
The value of a is: hello, world!
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