wrapping_macros

A macro for scoped wrapping arithmetic.

Any code within a wrapping! { .. } block will be transformed as follows:

• a + b becomes a.wrapping_add(b). Similarly for -, *, /, %, <<, >>.
• a += b becomes a = a.wrapping_add(b). Similarly for -=, *=, /=, %=, <<=, >>=.
• -a becomes a.wrapping_neg().

Cargo

Add this to your Cargo.toml:

toml wrapping_macros = "*"

Examples

```rust let a = 128u8; let b = wrapping! { a * 2 };

assert_eq!(b, 0); ```

```rust let mut a = 250u8; let mut b = 4u8; let mut c = 100u8; wrapping! { a += 10; b -= 10; c *= 10; }

asserteq!(a, 4); asserteq!(b, 250); assert_eq!(c, 232); ```

```rust use wrapping_macros::wrapping;

fn main() { let mut sum = 0u8; wrapping! { for x in 0u8..50 { sum += x; } } } assert_eq!(sum, 201); ```

Caveat

You cannot nest another macro invocation within a wrapping! block. For example, this will not work:

rust let x = 128u8; wrapping! { println!("The answer is {}", x + 128) // Error }

Instead, move the macro call out of the wrapping! block:

```rust let x = 128u8; println!("The answer is {}", wrapping! { x + 128 }) ````

Inspired by wrapping_macros crate by lfairy