From cmucl-devel at common-lisp.net  Fri Apr 28 16:57:45 2006
From: cmucl-devel at common-lisp.net (cmucl)
Date: Fri, 28 Apr 2006 16:57:45 -0000
Subject: [cmucl-ticket] [cmucl] #1: prin1 and ~E produce different outputs.
Message-ID: <076.7db2c3e210ca4a70e65ce806121e729d@common-lisp.net>

#1: prin1 and ~E produce different outputs.
------------------------+---------------------------------------------------
 Reporter:  anonymous   |       Owner:  somebody
     Type:  defect      |      Status:  new     
 Priority:  minor       |   Milestone:          
Component:  component1  |     Version:          
 Keywords:  printing    |  
------------------------+---------------------------------------------------
 (let ((x (random 1d-3)))
   (values (prin1-to-string x) (format nil "~E" x)))

 will produce different significant digits.  I think the problem is in ~E
 which calls lisp::scale-exponent to scale the number between 0.1 and 1.  I
 think we could just call flonum-to-digits which will give us the digits
 and the exponent.  We can massage that into the desired digits and
 exponent as in scale-exponent, but we won't have the round-off problem.

 Maybe.

-- 
Ticket URL: <http://trac.common-lisp.net/cmucl/ticket/1>
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