[comp.archives] [scheme] Re: Explode/Implode Query

jinx@zurich.ai.mit.edu (Guillermo J. Rozas) (04/23/91)

Archive-name: languages/scheme/sicp/1991-04-22
Archive: altdorf.ai.mit.edu:archive/scheme-7.1/sicp.tar.Z [18.43.0.246]
Original-posting-by: jinx@zurich.ai.mit.edu (Guillermo J. Rozas)
Original-subject: Re: Explode/Implode Query
Reposted-by: emv@msen.com (Edward Vielmetti, MSEN)

In article <1991Apr22.180734.21661@cunixf.cc.columbia.edu> betsey@cunixf.cc.columbia.edu (Elizabeth Fike) writes:

   Path: ai-lab!mintaka!think.com!zaphod.mps.ohio-state.edu!sol.ctr.columbia.edu!cunixf.cc.columbia.edu!betsey
   From: betsey@cunixf.cc.columbia.edu (Elizabeth Fike)
   Newsgroups: comp.lang.scheme
   Date: 22 Apr 91 18:07:34 GMT
   Sender: betsey@cunixf.cc.columbia.edu (Elizabeth Fike)
   Reply-To: betsey@cunixf.cc.columbia.edu
   Organization: Columbia University
   Lines: 14

   Today, in my Scheme class, the professor mentioned the functions
   explode and implode, are found in PC-Scheme, but in no
   other current versions of Scheme.  As these functions seem
   extremely useful, I am curious as to why they are not found in
   MIT Scheme version 7 (for example).  

   Thanks in advance!

   /betsey
   <betsey@cunixf.cc.columbia.edu>

   "I think that God's got a sick sense of humor
    And when I die, I expect to find him laughing" 
				   --Depeche Mode, "Blasphemous Rumors"

IMPLODE and EXPLODE are leftovers from older systems (MacLisp) that
are referred to in SICP (Structure and Interpretation of Computer
Programs by Abelson, Sussman, and Sussman), and (I believe) PC-Scheme
included them in order to be compatible.

MIT Scheme has evolved since the time when SICP was published and no
longer provides them in the standard load.  They are provided in the
SICP compatibility package.

MIT Scheme currently provides more useful alternatives.  You may want
to play with the following procedures:

write-to-string
with-output-to-string
with-output-to-truncated-string
with-string-output-port
with-input-from-string
string->input-port

You can get the SICP compatibility package for MIT Scheme 7.1 from
altdorf.ai.mit.edu:archive/scheme-7.1/sicp.tar.Z by anonymous ftp.


-- comp.archives file verification
altdorf.ai.mit.edu
-rw-rw-r--   1 5046     users      15455 Feb 14 19:29 archive/scheme-7.1/sicp.tar.Z
found sicp ok
altdorf.ai.mit.edu:archive/scheme-7.1/sicp.tar.Z