txt: ## mustbestarted.md
  class X::Proc::Async::MustBeStarted
  
  Error due to interacting with a Proc::Async stream before spawning its process
  
  ```raku
  class X::Proc::Async::MustBeStarted is Exception {}
  ```
  
  Several methods from [`Proc::Async`](/type/Proc/Async) expect that the external program has been spawned (by calling `.start` on it), including `say`, `write`, `print` and `close-stdin`. If one of those methods is called before `.start` was called, they throw an exception of type `X::Proc::Async::MustBeStarted`.
  
  ```raku
  Proc::Async.new('echo', :w).say(42);
  CATCH { default { put .^name, ': ', .Str } };
  # OUTPUT: «X::Proc::Async::MustBeStarted: Process must be started first before calling 'say'␤»
  ```
  
  # [Methods](#class_X::Proc::Async::MustBeStarted "go to top of document")[§](#Methods "direct link")
  
  ## [method method](#class_X::Proc::Async::MustBeStarted "go to top of document")[§](#method_method "direct link")
  
  ```raku
  method method(X::Proc::Async::MustBeStarted:D --> Str:D)
  ```
  
  Returns the name of the method that was illegally called before starting the external program.
  