agent-example.js

agent__xyz(ctx).on('change', (ctx) => {
  const {x,y,z} = ctx
})
agent__a(ctx).set({a:1})
function agent__xyz(ctx) {
  let agent = ctx.agent__xyz
  if (agent) return agent
  return ensure__agent(ctx, {
    key: 'agent__xyz',
    scope: ['x', 'y', 'z'],
    init() {
      agent = this
      agent__a(ctx).on('change', agent.reset)
    },
    async reset() {
      const {a} = ctx
          , everything = await everything__async()
          , z = a + 1 + everything
          , y = z + 1 + everything
          , x = y + 1 + everything
      agent.set({x, y, z})
    }
  })
  async function everything__async() {
    return 42
  }
}
function agent__xyz(ctx) {
  let agent = ctx.agent__xyz
  if (agent) return agent
  return ensure__agent(ctx, {
    key: 'agent__a',
    scope: ['a']
  })
}