core::traits::Drop - Starknet Documentation

A trait for types that can be safely dropped. Types implementing Drop can be automatically discarded when they go out of scope. The drop operation is a no-op - it simply indicates to the compiler that this type can be safely discarded.

Signature

pub trait Drop

Examples

Without Drop:

struct Point {
    x: u128,
    y: u128,
}

fn foo(p: Point) {} // Error: `p` cannot be dropped

With Drop:

#[derive(Drop)]
struct Point {
    x: u128,
    y: u128,
}

fn foo(p: Point) {} // OK: `p` is dropped at the end of the function