This branch refactors rewrite::apply and the Rewrite type's Display impl so that (1) the main "emit Rewrite" function is easier to extend (no more closures) and (2) the Display impl can reuse the rewrite::apply code so we don't have to implement every Rewrite variant twice. The precise design of the new Sink and Emitter types is not very clear, but it achieves the goals above and should work well enough for now.
This branch refactors
rewrite::applyand theRewritetype'sDisplayimpl so that (1) the main "emitRewrite" function is easier to extend (no more closures) and (2) theDisplayimpl can reuse therewrite::applycode so we don't have to implement everyRewritevariant twice. The precise design of the newSinkandEmittertypes is not very clear, but it achieves the goals above and should work well enough for now.