Subject: Re: A portable DIRECTORY-P. Re: Here we go again. More CMUCL/ACL pathname differences. From: Erik Naggum <erik@naggum.no> Date: 1999/01/18 Newsgroups: comp.lang.lisp Message-ID: <3125665755488131@naggum.no> * vnikolov@poboxes.com | I don't think CL wants to exclude file systems where the empty string is | a valid file name. (They would need some sort of escape character syntax | when parsing namestrings, of course, to denote such a (strange) file | name.) actually, I came across something that implies that the empty string and nothing are the same for a certain point of view: Parsing a null string always succeeds, producing a pathname with all components (except the host) equal to nil. this is in the dictionary for PARSE-NAMESTRING. so at least (file-namestring ...) => "" is reversible, but I'd still like to see some stronger wording to ensure that NIL is the correct answer. the dictionary for for PARSE-NAMESTRING doesn't say anything about when to return NIL now. for me, however, the intuitively evident is OK until people start to object. then I need something more concrete. sigh. the really pathetic thing here is that Unix used to treat the empty string as the current directory. that's how a trailing slash worked... #:Erik -- SIGTHTBABW: a signal sent from Unix to its programmers at random intervals to make them remember that There Has To Be A Better Way.