Path: utzoo!mnetor!uunet!husc6!bbn!rochester!PT.CS.CMU.EDU!IUS1.CS.CMU.EDU!edw
From: edw@IUS1.CS.CMU.EDU (Eddie Wyatt)
Newsgroups: comp.lang.c
Subject: Re: The D Programming Language: switches
Message-ID: <1186@PT.CS.CMU.EDU>
Date: 21 Mar 88 20:40:44 GMT
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Organization: Carnegie-Mellon University, CS/RI
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 >>
 >>Yes, in a sense switch is less powerful than an else-if chain.  Let's keep it,
 >>for the same reasons that we retain flow constructs less powerful than goto.
 >>
 > 	Theoretically the switch construct is more powerful than an else-if
 > chain because it selects in one step.  Execution is O(1) rather than O(n)
 > where n is the number of branches.  It is, for example, considerably more
 > efficient to use a switch with a thousand cases than an else-if chain with
 > a thousand elses.  [This is not to be taken as an endorsement of such
 > code. :-)]

  I think he meant in terms of expressability.  Which is true in a
practical sense, false in theorectically.  'switch' and 'else-if'
are equivalent in terms of expressability.


-- 

Eddie Wyatt 				e-mail: edw@ius1.cs.cmu.edu