WIP - Types

[usbalbin]

I think something like this should allow having more complex types as metrics. Not quite sure if Metric with its set/get is still appropriate for interacting with these more complex structures. Either way...

This allows deriving the Metricable trait for user structs which are in turn composed of only Metricable fields.

The type information is stored in a symbol which the tool can pick up and add to its lookup table. When the tool then sees a metric it would simply look up the type in the lookup table and generate a set of "primitive metrics" from that more complex type.

TODO:

• derive macro
• Update the tool to understand custom types
• arrays...
• Figure out how to use it from the target side - Metric or something else?
• Update/add examples
• Make the code pretty

[usbalbin]

Another thought, what about something like this?

#[derive(Plottable)]
struct Foo {
    #[metric("bar / 33.1")]
    bar: u8,

    baz: Baz,

    #[setting(0..=3, 1)]
    quix: f32
}

#[derive(Plottable)]
struct Baz {
    #[metric("a * 3.0")]
    a: i16
}