Path: utzoo!mnetor!uunet!husc6!bbn!rochester!udel!princeton!mind!eliot
From: eliot@mind.UUCP (Eliot Handelman)
Newsgroups: comp.lang.lisp
Subject: Re: query 'bout defstruct (Common LISP)
Message-ID: <2408@mind.UUCP>
Date: 3 May 88 01:35:05 GMT
References: <10834@cgl.ucsf.EDU] <786@hydra.riacs.edu>
Reply-To: eliot@mind.UUCP (Eliot Handelman)
Organization: Bad Sounding Music, Inc
Lines: 29
Keywords: setf, gentemp, clarity

In article <786@hydra.riacs.edu] nienart@turing.arc.nasa.gov.UUCP (john nienart) writes:
]In article <10834@cgl.ucsf.EDU> yee@cgl.ucsf.edu (dave yee) writes:
]>
]>Now, i figured i could use "gentemp" to make the symbols,
]>but i can't "setq" these new symbols (i.e.
]>(setq (gentemp) (make-piece)) just doesn't cut it...
]>
]How about (setf (symbol-value (gentemp)) (make-piece))? This gets the
]effect you want. However, you don't have a handle on the name after
]this, so you probably want something like:
]
](let ((sym (gentemp)))
]  (setf (symbol-value sym) (make-piece))
]  ...)
]which gives SYM a value which is the name of your piece. Symbol-value can 
]access it then.


Why not just use (set (gentemp) (make-piece))? It does the same thing without
bothering to hunt down the setf method. If you need the handle you can either
use LET or have the new name returned as a second value:

(defun set-gentemp (form)
  (let ((sym (gentemp)))
   (values (set sym form) sym)))
 
Best wishes,

Eliot Handelman