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  Directive:  #define
 
  Syntax:     #define identifier substitution-text
              #define identifier([parameter-list]) substitution-text
 
  Summary:    Replaces all subsequent cases of <identifier> with
              the <substitution-text>.
 
  See also:   defined, #if, #ifdef, #ifndef, #undef
 
     The <substitution-text> can consist of one or more constants,
     keywords, or statements. When the identifier is replaced by a
     constant expression, it is known as a manifest constant. When the
     identifier is replaced by an expression containing parameters, it
     is known as a macro.
 
     If the <substitution-text> is more than one line, it can be
     continued onto successive lines by placing a backslash (\) before
     the end of each line. Enclosing the <substitution-text> in
     parentheses ensures proper evaluation if the text is an
     expression, or has a leading minus sign. The <substitution-text>
     can also be empty; this removes occurrences of the identifier from
     the file.
 
     If a <parameter-list> appears after the identifier, each
     occurrence of <identifier>(<actual-parameter-list>) is replaced by
     a version of the <substitution-text> that has actual arguments
     substituted for the formal parameters. There must be an equal
     number of actual arguments and formal parameters.
 
     The optional <parameter-list> consists of one or more formal
     parameter names, separated by commas and enclosed by parentheses.
     No space can separate the identifier and the opening parenthesis.
     The formal parameter names appear in the <substitution-text> to
     mark the places where actual values will be substituted.
 
     Macros may also use the preprocessor operators.
 
     See: ◄Stringizing Operator►
          ◄Charizing Operator►
          ◄Token-Pasting Operator►
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