But not all of them are equivalent. Push flows can deal with multiple sinks while pull flows can deal with multiple sources for instance. It's totally reasonabl

But not all of them are equivalent. Push flows can deal with multiple sinks while pull flows can deal with multiple sources for instance. It's totally reasonable to mix these if you match their flows (or have unlimited memory to buffer stuff). Ideally the compiler could figure out a data flow that runs in constant space from a declarative program. There are some papers into that direction but afair we aren't there ysr.