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const generics

Generics over a value, like an array's length, instead of a type.

A const generic parameter (const N: usize) makes an item generic over a compile-time constant, as in [T; N].

Examples

  • fn sum<const N: usize>(xs: [i32; N]) -> i32 accepts both [1, 2] and [1, 2, 3], with N inferred as 2 and 3.

See also

generics array monomorphization
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