diff --git a/csp/sync.csp b/csp/sync.csp index 4ad64a7..d864493 100644 --- a/csp/sync.csp +++ b/csp/sync.csp @@ -4,15 +4,22 @@ channel input, render, up, down, save, saved:STATES apply(state, patch) = (state + patch) % S diff(state1, state2) = (state2 - state1) % S +empty(patch) = patch == 0 CLIENT(i, state, shadow) = input?new_state -> up!diff(shadow, new_state) -> CLIENT(i, new_state, shadow) [] down?patch - -> if patch != 0 - then render!apply(state, patch) -> CLIENT(i, apply(state, patch), apply(shadow, patch)) - else CLIENT(i, state, state) + -> if empty(patch) + then CLIENT(i, state, state) + else + if diff(apply(shadow, patch), apply(state, patch)) != 0 + then up!diff(apply(shadow, patch), apply(state, patch)) + -> render!apply(state, patch) + -> CLIENT(i, apply(shadow, patch), apply(state, patch)) + else render!apply(state, patch) + -> CLIENT(i, apply(shadow, patch), apply(state, patch)) SERVER(i, shadow) = up?patch