3 Things that the Rust Standard Library should have…

9

The HashMap::from([...]) thing is relatively new (it appeared in rust 1.56). So maybe there will be a macro to improve the syntax even more sometime soon? On the other hand, maybe that generic "create a map" macro would not give that much benefit anyway, compared to a more specific macro, that could be a part of some used crate, or that you could implement yourself.

E.g. something like this:

    let data2 = graph![
        0 => 1, 2;
        1 => 0, 2;
        2 => 0, 1, 3, 5;
        3 => 2, 4;
        4 => 3;
        5 => 2, 6, 8;
        6 => 5, 7;
        7 => 6, 8;
        8 => 5, 7
    ];

... is not that hard to create with a macro of your own (playground link) (In my example it just creates a hashmap, in a graph crate it would probably create a graph type that may use a hashmap (or a BTreeMap) for its implementation).

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