Re: Generalizing find-definition

[Helmut Eller]

> Too bad that classes can't be autoloaded.

I added this little hack to autoload classes:

  (defvar xref-backend 'etags-xref-backend
    "The class symbol used to create backend instances.
  It should be a subclass of `xref-backend-class'.
  The front-end calls `make-instance' with this symbol as argument.")
  
  (defun xref--maybe-autoload-class (symbol)
    (unless (class-p symbol)
      (let ((f (symbol-function symbol)))
        (when (autoloadp f)
        (autoload-do-load f symbol)))))
  
  (defun xref--backend ()
    (let ((symbol xref-backend))
      (xref--maybe-autoload-class symbol)
      (make-instance symbol)))

And an autoloadable class is then defined as:

  ;;;###autoload (autoload 'etags-xref-backend "etags")
  (defclass etags-xref-backend (xref-backend-class eieio-singleton) ())

This works because defclass creates a constructor function
with the same name as the classname.

Would this be acceptable, from a style point of view?

Helmut