proposal: local

[betula]

cosnt v = value(0);

v.flow((value) => {
  const ticket = local(() => wait(k));
  if (!ticket.val) return flow.stop();
  return value;
});

v.flow.filter(() => {
  return local(() => wait(k)).val
});

local(expr) // <- bind only first time not necessary bind it every time
                   // if you need bind every time you should use plain function not local expression.
                   // synonim of local(expr, []);
local(expr, [<real value dep>, ...])
local(expr, <refresh symbol or expression>);

// or all combination of that
local(expr, <refresh symbol or expression>, [<real value dep>, ...]);
local(expr, [<real value dep>, ...], <refresh symbol or expression>);

[betula]

Added to "the stream of conciseness 0.7+ roadmap"