Code coverage for safe_equal.li

///////////////////////////////////////////////////////////////////////////////
//                             Lisaac Library                                //
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///////////////////////////////////////////////////////////////////////////////
Section Header

  + name    := SAFE_EQUAL(E);


  - copyright   := "2003-2005 Jérome Boutet, 2003-2007 Benoit Sonntag";

  - comment :="The goal of this class is to share the definition of \
              \feature `safe_equal'. Feature `safe_equal' compares  \
              \two arguments of type E, by calling `==' only  \
              \and only if both arguments have the `same_type'..";

Section Inherit

  - parent:OBJECT := OBJECT;

Section Public

  - safe_equal (e1, e2:E) :BOOLEAN <-
  // In order to avoid run-time type errors, feature `safe_equal' call
  // `==' only when `e1' and `e2' have exactly the same `generating_type'.
  // Furthermore, this feature avoid argument passing from some
  // expanded type to the corresponding reference type (no automatic
  // allocation of some reference type during the comparison).
  ( /*
    + result:BOOLEAN;

    ( e1.is_basic_expanded_type).if { then
      result := (e1 = e2);
    }.elseif {e1.is_expanded_type} then {
      result := e1 == e2;
    }.elseif {e1 = e2} then {
      result := true;
    }.elseif {(e1 = NULL) || {e2 = NULL}} then {
    }.elseif {e1.generating_type = e2.generating_type} then {
      result := e1 == e2;
    }; // end if

    result
    */
    (e1=e2) || {(e1!=NULL)    {e1==e2}}
  );