From mboxrd@z Thu Jan 1 00:00:00 1970 Received: (from majordomo@localhost) by pauillac.inria.fr (8.7.6/8.7.3) id UAA32134; Fri, 31 May 2002 20:22:11 +0200 (MET DST) X-Authentication-Warning: pauillac.inria.fr: majordomo set sender to owner-caml-list@pauillac.inria.fr using -f Received: from concorde.inria.fr (concorde.inria.fr [192.93.2.39]) by pauillac.inria.fr (8.7.6/8.7.3) with ESMTP id UAA32055 for ; Fri, 31 May 2002 20:22:09 +0200 (MET DST) Received: from sunny.pacific.net.au (sunny.pacific.net.au [203.25.148.40]) by concorde.inria.fr (8.11.1/8.11.1) with ESMTP id g4VIM7527018 for ; Fri, 31 May 2002 20:22:07 +0200 (MET DST) Received: from wisma.pacific.net.au (wisma.pacific.net.au [210.23.129.72]) by sunny.pacific.net.au with ESMTP id g4VIM2Zr022617; Sat, 1 Jun 2002 04:22:02 +1000 (EST) Received: from ozemail.com.au (ppp10.dyn17.pacific.net.au [61.8.17.10]) by wisma.pacific.net.au with ESMTP id EAA25375; Sat, 1 Jun 2002 04:22:00 +1000 (EST) Message-ID: <3CF7BF45.40201@ozemail.com.au> Date: Sat, 01 Jun 2002 04:21:57 +1000 From: John Max Skaller User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:0.9.2.1) Gecko/20010901 X-Accept-Language: en-us MIME-Version: 1.0 To: Warp CC: Jacques Garrigue , OCaml Subject: Re: [Caml-list] about Obj.magic References: <003601c20884$0d78efd0$7900a8c0@warp> <20020531225840C.garrigue@kurims.kyoto-u.ac.jp> <00b401c208ac$4d0eae00$7900a8c0@warp> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-caml-list@pauillac.inria.fr Precedence: bulk An 'almost legal' use of Obj.magic is to populate an array with dummy values. For example: class Deep .. let a = Array.make 100 (Obj.magic 0 :> Deep) in let len_a = ref 0 in This is roughly as safe as an unsafe array access, only now the array length is a variable. -- John Max Skaller, mailto:skaller@ozemail.com.au snail:10/1 Toxteth Rd, Glebe, NSW 2037, Australia. voice:61-2-9660-0850 ------------------- To unsubscribe, mail caml-list-request@inria.fr Archives: http://caml.inria.fr Bug reports: http://caml.inria.fr/bin/caml-bugs FAQ: http://caml.inria.fr/FAQ/ Beginner's list: http://groups.yahoo.com/group/ocaml_beginners