txt: ## bindoruse.md
  class X::Proc::Async::BindOrUse
  
  Error due to trying to bind a handle that is also used
  
  ```raku
  class X::Proc::Async::BindOrUse does X::Proc::Async {}
  
  ```
  
  In general, it occurs when there's some mistake in the direction the stream flows, for instance:
  
  ```raku
  my $p = Proc::Async.new("ls", :w);
  my $h = "ls.out".IO.open(:w);
  $p.bind-stdin($h);
  # Fails with OUTPUT: «Cannot both bind stdin to a handle and also use :w␤»
  
  ```
  
  In this case, `stdin` is already bound and cannot be used again; one of them should flow `:out` and the other one `:w` to work correctly.
  