What i64x32 does
i64x32 is a type alias exposed by the std::simd::prelude module of the Rust standard library. It is part of the public, stable API and you can rely on it from any edition of Rust.
type i64x32 = ... introduces a new name for an existing type. The alias is purely a syntactic shortcut — it does not create a distinct type. Use i64x32 anywhere you would write the underlying type. The full canonical path is std::simd::prelude::i64x32; bring it into scope with use std::simd::prelude::i64x32; or refer to it by its full path.
When to use it
Use i64x32 as a shorter name for its underlying type. Type aliases do not create new types — they're purely for readability and future-proofing.
Annotated examples
Declaring values of type i64x32
use std::simd::prelude::i64x32;
fn demo() {
// i64x32 is a type alias — it desugars to its underlying type but
// gives you a meaningful name to read and write. Type aliases do not
// create new types; they're purely for readability.
let value: i64x32 = Default::default();
let _ = value;
}
Type aliases shorten verbose generic types in your own APIs (e.g. `type Result<T> = std::result::Result<T, MyError>;`) and give domain-specific names to common shapes.
For deeper background, see the canonical Rust patterns reference for the broader context behind this section.
Using i64x32 in a function signature
use std::simd::prelude::i64x32;
// A type alias makes the function signature self-documenting and lets
// you swap the underlying representation in one place if requirements
// change.
fn process(input: i64x32) -> i64x32 {
input
}
Aliases work in any position a regular type does — function arguments, return values, generic parameters. They're a cheap way to make code more readable.
Common pitfalls
A type alias is not a new type — it does not enforce different semantic intent. If you want the compiler to distinguish two different shapes that share the same underlying representation, use a newtype struct instead.
For deeper background, see an in-depth Rust idioms cheat sheet for the broader context behind this section.
Performance & threading notes
Pure compile-time. The alias is erased before code generation; the resulting binary is identical to one that uses the underlying type directly.