A situation I've encountered several times already is implementing statically sized FIFOs. At the moment in Rust I can't implement a type "FIFO of depth N" where is a generic, static parameter. My only choices are implementing "FIFO of depth n" where n is provided dynamically at runtime (and implemented internally using something like a VecDeque) or a completely fixed depth FIFO type that I need to duplicate for every depth (FIFO32, FIFO16, FIFO10 etc...).

If you require very high performance a dynamically checked FIFO can incur a fairly large overhead when a well optimized static FIFO can implement most operations in a couple of opcodes at most.