;;; -*- mode: Lisp; Syntax: Common-Lisp; -*-
;;;
;;; Copyright (c) 2009 by the authors.
;;;
;;; See LICENCE for details.

(in-package :hu.dwim.projectional-editor)

;;;;;;;
;;; Reader API

(def (generic e) read-from-device (document device)
  (:documentation "Reads an operation in the context of DOCUMENT from a single DEVICE. Has side effects on DEVICE."))

(def (namespace e) reader)

(def (definer e) reader (name arguments &body forms)
  `(setf (find-reader ',name) (lambda ,arguments ,@forms)))

;;;;;;
;;; Reader API implementation

(def method read-from-device (object (device device/output))
  ;; NOTE: continue if DEVICE is also an input device, otherwise do nothing
  (if (input-device? device)
      (call-next-method)
      (values)))