Call(F:FUNCTION, X_1,...,X_n):OBJECT

where X_1,...,X_n are the arguments for the function F.

  -- The following function MyMax takes a function LessThan as parameter,
  -- and returns the maximum of X and Y w.r.t. the ordering defined by the
  -- function LessThan.

  Define MyMax(LessThan, X, Y)
    If Call(LessThan, X, Y) Then Return Y Else Return X EndIf
  EndDefine;

  -- Let's use MyMax by giving two different orderings.

  Define LT_Standard(X, Y)
    Return X < Y;
  EndDefine;
  Define LT_First(X, Y)
    Return TRUE;
  EndDefine;

  MyMax(Function("LT_Standard"),3,5);
5
-------------------------------
  MyMax(Function("LT_First"),5,3);
3
-------------------------------
  MyMax(Function("LT_First"),3,5);
5
-------------------------------
  MyMax(Function("LT_First"),5,3);
3
-------------------------------