As with many things in life, it's a tradeoff, not a replacement :) Specs don't run at compile-time (except for macros), but they are more flexible than static t

As with many things in life, it's a tradeoff, not a replacement :) Specs don't run at compile-time (except for macros), but they are more flexible than static types. Apart from runtime instrumentation, they can be used to validate or destructure complicated data (read from the wire or disk, for example), and they can generate tests automatically.