C/the.ansi.c.programming.language/c.programming.notes/sx14c.html

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  15 <H2>Statements</H2>
  16
  17 <p>The <TT>switch</TT> statement allows you to jump to one of a
  18 number of numeric <TT>case</TT> labels depending on the value of
  19 an expression;
  20 it's more convenient than a long <TT>if</TT>/<TT>else</TT> chain.
  21 (However, you can use <TT>switch</TT>
  22 only when the expression is integral
  23 and all of the <TT>case</TT> labels are compile-time constants.)
  24 </p><p>The <TT>do</TT>/<TT>while</TT> loop
  25 is a loop that tests its controlling expression
  26 at the bottom of the loop,
  27 so that the body of the loop always executes once
  28 even if the condition is initially false.
  29 (C's <TT>do</TT>/<TT>while</TT> loop is therefore like
  30 Pascal's <TT>repeat</TT>/<TT>until</TT> loop,
  31 while
  32
  33 C's <TT>while</TT> loop is like Pascal's <TT>while</TT>/<TT>do</TT> loop.)
  34 </p><p>Finally,
  35 when you really need to write ``spaghetti code,''
  36 C does have the all-purpose <TT>goto</TT> statement,
  37 and labels to go to.
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