Warning: Invalid argument
  In file `sets/sets-impl.scm:1321',
  At the toplevel,
  In procedure call:

    (chicken.read-syntax#set-sharp-read-syntax!
      'bag
      (lambda (port) (let (...) (##sys#list ... ...))))

  Argument #1 to procedure `set-sharp-read-syntax!' has an invalid type:

    symbol

  The expected type is:

    char

  This is the expression:

    'bag

  Procedure `set-sharp-read-syntax!' from module `chicken.read-syntax' has this type:

    (char (or false (procedure (input-port) . *)) -> undefined)