C/the.ansi.c.programming.language/notes.accompany.ansi.c/sx4g.html

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   9 <title>section 1.5.2: Character Counting</title>
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  15 <H2>section 1.5.2: Character Counting</H2>
  16
  17 page 18
  18 <p>Ignore the mention of efficiency with respect to
  19 <TT>nc = nc+1</TT> vs. <TT>++nc</TT>.
  20 Once you've gotten used to <TT>++</TT> meaning ``increment by 1,''
  21 you'll probably find yourself preferring <TT>++nc</TT>
  22 simply because it is more concise,
  23 and incrementing things by 1 is so common.
  24 (Personally,
  25 once I got used to it,
  26 I found <TT>++</TT> more natural, too,
  27 because after all,
  28 expressions like <TT>nc = nc+1</TT>,
  29 though they're common enough in programming,
  30 are very unnatural from an algebraic perspective.)
  31 </p><p>pages 18-19
  32 </p><p>You may find it odd to have a loop with no body,
  33 but such loops do crop up.
  34 Just make sure that the explicit null statement
  35 (or, if you prefer, empty <TT>{}</TT>)
  36 marking the empty loop body is plainly visible.
  37 </p><p>The whole first paragraph of page 19 counts as ``deep.''
  38 A clean, well-designed loop will work properly for all of its
  39 ``boundary conditions'':
  40 zero trips through the loop,
  41 one trip,
  42 many trips,
  43 maximum trips
  44 (if there is any maximum,
  45 and if so, also maximum minus one).
  46 If a loop for some reason doesn't work at a particular boundary condition,
  47 it's tempting to claim that that condition is rare or
  48 impossible and that the loop is therefore okay.
  49 But if
  50 the loop
  51 can't handle
  52 the boundary condition,
  53 why can't it?
  54 It's probably awkwardly constructed,
  55 and straightening it out so
  56 that it naturally handles all boundary conditions
  57 will usually make it clearer and easier to understand
  58 (and may also remove other lurking bugs).
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  68 This page by <a href="http://www.eskimo.com/~scs/">Steve Summit</a>
  69 // <a href="copyright.html">Copyright</a> 1995, 1996
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