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Inherent Unchecked Integer Methods in Rust

Core Problem

The unchecked_* methods on integers have been implemented as part of the Rust language, but their inherent nature has raised questions about their stability and usability.

Solution & Analysis

impl u32 {
    pub const unsafe fn unchecked_add(self, rhs: u32) -> u32;
    pub const unsafe fn unchecked_sub(self, u32) -> u32;
    pub const unsafe fn unchecked_mul(self, u32) -> u32;
}
impl i32 {
    pub const unsafe fn unchecked_add(self, rhs: i32) -> i32;
    pub const unsafe fn unchecked_sub(self, i32) -> i32;
    pub const unsafe fn unchecked_mul(self, i32) -> i32;
}

// ...

impl u64 {
    pub const unsafe fn unchecked_add(self, rhs: u64) -> u64;
    pub const unsafe fn unchecked_sub(self, u64) -> u64;
    pub const unsafe fn unchecked_mul(self, u64) -> u64;
}

The unchecked_* methods are used to perform operations on integers without checking for overflow or underflow. However, this comes at the cost of safety and reliability.

Conclusion

The implementation of inherent unchecked_* methods in Rust provides a performance boost for certain use cases, but it also raises questions about their stability and usability. As the language continues to evolve, it is essential to carefully consider the implications of such features and ensure that they align with the goals of the Rust project.

Reference