Path: utzoo!attcan!uunet!littlei!intelisc!omepd!merlyn
From: merlyn@intelob.intel.com (Randal L. Schwartz @ Stonehenge)
Newsgroups: comp.emacs
Subject: Re: Is a file loadable?
Message-ID: <3779@omepd>
Date: 2 Sep 88 16:30:24 GMT
References: <5852@columbia.edu> <36722@yale-celray.yale.UUCP> <1140@titan.SW.MCC.COM>
Sender: news@omepd
Reply-To: merlyn@intelob.intel.com (Randal L. Schwartz @ Stonehenge)
Organization: Stonehenge; netaccess via BiiN, Hillsboro, Oregon, USA
Lines: 36
In-reply-to: janssen@titan.sw.mcc.com (Bill Janssen)

In article <1140@titan.SW.MCC.COM>, janssen@titan (Bill Janssen) writes:
| [some nice lisp code]

Here's one that's a little shorter (and probably more robust) that I
wrote after seeing Bill's code.  Purists will want to change the
"'(lambda ...)"s to "(function (lambda ...))"s, but I'm not compiling
this one yet.  Note that this one properly handles the "nil" in the
load-path, and the NOSUFFIX flag of load.

(defun which-load (file &optional nosuffix)
  "Find out which FILE would be loaded with the current `load-path'.
Return a string representing the absolute path-name of the file that
would be loaded with a `load' command, or nil if no such file exists.
If optional NOSUFFIX is non-nil, don't try adding suffixes .elc or .el
to the specified name FILE (ala `load').  This function cannot test
the contents of the file for appropriateness to be loaded, but neither
does `load'."
  (catch 'answer
    (mapcar
     '(lambda (dir)
	(mapcar
	 '(lambda (suf)
	    (let ((try (expand-file-name (concat file suf) dir)))
	      (and (file-readable-p try)
		   (null (file-directory-p try))
		   (throw 'answer try))))
	 (if nosuffix '("") '(".elc" ".el" ""))))
     load-path)
    nil))

Yours for a better tomorrow,
-- 
Randal L. Schwartz, Stonehenge Consulting Services (503)777-0095
on contract to BiiN Technical Publications (for now :-), Hillsboro, Oregon
<merlyn@intelob.intel.com> or ...!tektronix!inteloa[!intelob]!merlyn
Standard disclaimer: I *am* my employer!