edf50fdf80
- Run mix credo --all to identify possible code optimizations - Resolve most of the errors generated by credo such as: - Numbers larger than 9999 should be written with underscores: 58_127 - Modules should have a @moduledoc tag - Comparison will always return true
47 lines
1.2 KiB
Elixir
47 lines
1.2 KiB
Elixir
defmodule Agents do
|
|
@moduledoc false
|
|
use Koans
|
|
|
|
@intro "Agents"
|
|
|
|
koan "Agents maintain state, so you can ask them about it" do
|
|
{:ok, pid} = Agent.start_link(fn -> "Hi there" end)
|
|
assert Agent.get(pid, & &1) == ___
|
|
end
|
|
|
|
koan "Agents may also be named so that you don't have to keep the pid around" do
|
|
Agent.start_link(fn -> "Why hello" end, name: AgentSmith)
|
|
assert Agent.get(AgentSmith, & &1) == ___
|
|
end
|
|
|
|
koan "Update to update the state" do
|
|
Agent.start_link(fn -> "Hi there" end, name: :greeter)
|
|
|
|
Agent.update(:greeter, fn old ->
|
|
String.upcase(old)
|
|
end)
|
|
|
|
assert Agent.get(:greeter, & &1) == ___
|
|
end
|
|
|
|
koan "Use get_and_update when you need to read and change a value in one go" do
|
|
Agent.start_link(fn -> ["Milk"] end, name: :groceries)
|
|
|
|
old_list =
|
|
Agent.get_and_update(:groceries, fn old ->
|
|
{old, ["Bread" | old]}
|
|
end)
|
|
|
|
assert old_list == ___
|
|
assert Agent.get(:groceries, & &1) == ___
|
|
end
|
|
|
|
koan "Somebody has to switch off the light at the end of the day" do
|
|
{:ok, pid} = Agent.start_link(fn -> "Fin." end, name: :stoppable)
|
|
|
|
Agent.stop(:stoppable)
|
|
|
|
assert Process.alive?(pid) == ___
|
|
end
|
|
end
|