Crate nonn

nonn

Integer types that are known not to equal any single N, enabling some memory layout optimization.

Most of nonn’s code is lifted from core::num::nonzero and slightly adapted.

nonn is backed by core::num::NonZero*, ensuring

use std::mem::size_of;

assert_eq!(size_of::<Option<nonn::NonNU8<0>>>(), size_of::<u8>());
assert_eq!(size_of::<Option<nonn::NonNU16<1>>>(), size_of::<u16>());
assert_eq!(size_of::<Option<nonn::NonNU32<2>>>(), size_of::<u32>());
assert_eq!(size_of::<Option<nonn::NonNU64<3>>>(), size_of::<u64>());
assert_eq!(size_of::<Option<nonn::NonNU128<4>>>(), size_of::<u128>());
assert_eq!(size_of::<Option<nonn::NonNUsize<5>>>(), size_of::<usize>());
assert_eq!(size_of::<Option<nonn::NonNI8<6>>>(), size_of::<i8>());
assert_eq!(size_of::<Option<nonn::NonNI16<7>>>(), size_of::<i16>());
assert_eq!(size_of::<Option<nonn::NonNI32<8>>>(), size_of::<i32>());
assert_eq!(size_of::<Option<nonn::NonNI64<9>>>(), size_of::<i64>());
assert_eq!(size_of::<Option<nonn::NonNI128<10>>>(), size_of::<i128>());
assert_eq!(size_of::<Option<nonn::NonNIsize<11>>>(), size_of::<isize>());

nonn functions in no_std environments.

Limitations

NonN* types will inevitably introduce many branches in most methods. If you require higher performance, it is advisable to use either core::num::nonzero or the nonmax crate. These alternative options are more specialized and can thus avoid many of the checks nonn uses.

nonn currently does not implement Neg for its types, as Neg on NonNU*<N> should in theory result in NonNI*<-N>. This is currently not possible to my knowledge, even on nightly.

nonn requires at least Rust 1.57.0 to compile, but 1.67.0 or above is required for ilog2 and ilog10.

Structs

• NonNI8
  8-bit signed integer type that is known not to equal to any single value N.
• NonNI16
  16-bit signed integer type that is known not to equal to any single value N.
• NonNI32
  32-bit signed integer type that is known not to equal to any single value N.
• NonNI64
  64-bit signed integer type that is known not to equal to any single value N.
• NonNI128
  128-bit signed integer type that is known not to equal to any single value N.
• NonNIsize
  Pointer-sized signed integer type that is known not to equal to any single value N.
• NonNU8
  8-bit unsigned integer type that is known not to equal to any single value N.
• NonNU16
  16-bit unsigned integer type that is known not to equal to any single value N.
• NonNU32
  32-bit unsigned integer type that is known not to equal to any single value N.
• NonNU64
  64-bit unsigned integer type that is known not to equal to any single value N.
• NonNU128
  128-bit unsigned integer type that is known not to equal to any single value N.
• NonNUsize
  Pointer-sized unsigned integer type that is known not to equal to any single value N.