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   9 <title>2.4 Variable Names</title>
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  15 <H2>2.4 Variable Names</H2>
  16
  17 <p>[This section corresponds to K&amp;R Sec. 2.1]
  18 </p><p>Within limits, you can give your variables
  19 and functions
  20 any names you want.
  21 These names
  22 (the formal term is ``identifiers'')
  23 consist of letters, numbers, and underscores.
  24 For our purposes, names must begin with a letter.
  25 Theoretically,
  26 names can be as long as you want,
  27 but extremely long ones get tedious to type after a while,
  28 and the compiler is not required to keep track of extremely
  29 long ones perfectly.
  30 (What this means is that if you were to name a variable, say,
  31 <TT>supercalafragalisticespialidocious</TT>,
  32 the compiler might get lazy and pretend that you'd named it
  33 <TT>supercalafragalisticespialidocio</TT>,
  34 such that if you later misspelled it
  35 <TT>supercalafragalisticespialidociouz</TT>,
  36 the compiler wouldn't catch your mistake.
  37 Nor would the compiler necessarily be able to tell the
  38 difference if for some perverse reason you <em>deliberately</em>
  39 declared a second variable named
  40 <TT>supercalafragalisticespialidociouz</TT>.)
  41
  42 </p><p>The capitalization of names in C is significant:
  43 the variable names <TT>variable</TT>, <TT>Variable</TT>, and
  44 <TT>VARIABLE</TT>
  45 (as well as silly combinations like <TT>variAble</TT>)
  46 are all distinct.
  47 </p><p>A final restriction on names is that you may not use <dfn>keywords</dfn>
  48 (the words such as <TT>int</TT> and <TT>for</TT>
  49 which are part of the syntax of the language)
  50 as the names of variables or functions
  51 (or as identifiers of any kind).
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  61 This page by <a href="http://www.eskimo.com/~scs/">Steve Summit</a>
  62 // <a href="copyright.html">Copyright</a> 1995, 1996
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