Instrument a function.

def call do
  Appsignal.instrument("foo.bar", fn ->
    :timer.sleep(1000)
  end)
end

When passing a function that takes an argument, the function is called with the created span to allow adding extra information.

def call(params) do
  Appsignal.instrument("foo.bar", fn span ->
    Appsignal.Span.set_sample_data(span, "params", params)
    :timer.sleep(1000)
  end)
end