# 057: Event Emitters
# Send custom events

# Define events
on_user_login(user):
  emit event "user.logged_in" with { user }

on_purchase(item, price):
  emit event "purchase.completed" with { item, price }

on_error(message):
  emit event "app.error" with { message }

# Trigger events
button "Login" -> login()
button "Buy Item" -> buy()
button "Cause Error" -> cause_error()

login():
  user = { name: "Alex", id: 123 }
  on_user_login(user)

buy():
  on_purchase("Coffee Mug", 12.99)

cause_error():
  on_error("Something went wrong!")

# Events can be caught by listeners (see next example)
# This allows decoupled communication between parts of your app