sumtype 0.3.0

[jmh530]

On Sunday, 6 May 2018 at 19:18:02 UTC, Paul Backus wrote:
> [snip]
>   - Zero runtime overhead compared to hand-written C

Just to clarify, would the run-time performance of the length 
function in the example be equivalent to if it had been 
specialized for the Rectangular types (e.g. double 
length(Rectacular r) { ... })? It looks like the match is using 
compile-time functionality to choose the right function to call, 
but I wanted to be sure.