[climacs-devel] Re: a patch for climacs (mainly regarding COMPLETABLY-PATHNAME) + a gimmick

[Robert Strandh]

Max-Gerd Retzlaff writes:
 > I propose that COM-SHOW-DIRECTORY should become a general PRESENT method
 > for a presentation LIST OF PATHNAMES, as well as the construct
 > 
 > (let ((icon (clim-listener::icon-of pathname)))
 >       (when icon
 >         (clim-listener::draw-icon stream icon :extra-spacing 30)))
 >     (princ (clim-listener::pathname-printing-name pathname long-name) stream))
 > 
 > should be CLIM's general PRESENT method for PATHNAME in TEXTUAL-DIALOG-VIEW.
 > (The latter is already defined in file-selector.lisp.)

This code has a problem (aside from the very unfortunate indentation),
namely that it assumes that the listener is present.  At the moment, I
do not think that is a good idea. 

This is going to be a general problem for other applications as well.
We are often going to want code that means "if this package exists and
this symbol has a function definition in that package, then call the
function with the following arguments" .  Perhaps a macro
FUNCALL-IN-PACKAGE like this:

  (funcall-in-package :clim-listener (#:icon-of pathname)
     (message "sorry..."))

 > PS: Should this discussion be on mcclim-devel instead?

Maybe so, yes. 
-- 
Robert Strandh

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