Impl Send for Symbolizer?

[d-e-s-o]

In some contexts it would be great to have Symbolizer (and, perhaps slightly less importantly, Inspector and Normalizer) be Send. I prototyped that here https://github.com/d-e-s-o/blazesym/compare/main..topic/symbolizer-send but it requires usage of a bunch of more heavy weight synchronization primitives. It's an open question whether we want to pay that price.

[d-e-s-o]

I think one thing we could do to eliminate the need for some of those synchronization primitives would be to make the caching we do explicit in method signatures. That is, symbolize(&self, [...]) -> symbolize(&mut self, [...]). Not sure what negative trickle down effects that would have on clients.

[danielocfb]

Not sure what negative trickle down effects that would have on clients.

One of the obvious downsides would be that, because we effectively return borrowed data from Symbolizer::symbolize, this data would have to be dropped (or cloned) before to the next call to symbolize. I think that disqualifies this approach.