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/Rust

Error code E0308

Expected type did not match the received type.

Erroneous code examples:

#![allow(unused)]
fn main() {
fn plus_one(x: i32) -> i32 {
    x + 1
}

plus_one("Not a number");
//       ^^^^^^^^^^^^^^ expected `i32`, found `&str`

if "Not a bool" {
// ^^^^^^^^^^^^ expected `bool`, found `&str`
}

let x: f32 = "Not a float";
//     ---   ^^^^^^^^^^^^^ expected `f32`, found `&str`
//     |
//     expected due to this
}

This error occurs when an expression was used in a place where the compiler expected an expression of a different type. It can occur in several cases, the most common being when calling a function and passing an argument which has a different type than the matching type in the function declaration.

© 2010 The Rust Project Developers
Licensed under the Apache License, Version 2.0 or the MIT license, at your option.
https://doc.rust-lang.org/error_codes/E0308.html