const-struct-version 0.2.0

A trait plus proc-macro to generate a hash based on the fields of a struct. Useful for intelligently expiring a cache when the stored object changes.
Documentation 
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#![allow(dead_code)]

use const_struct_version::StructVersion;

// TODO: Eventually I'd like named fields to be sorted by field name, so they are consistent across
// differnet orderings.

#[derive(StructVersion)]
struct NamedFieldsStruct {
    a: u32,
    b: f32,
}

#[derive(StructVersion)]
struct NamedFieldsStruct2 {
    b: f32,
    a: u32,
}

#[test]
fn test_that_versions_are_different() {
    let version = <NamedFieldsStruct as StructVersion>::version();
    let version2 = <NamedFieldsStruct2 as StructVersion>::version();

    insta::assert_debug_snapshot!(version);
    insta::assert_debug_snapshot!(version2);

    // Ensure all are different.
    assert_ne!(version, version2);
}