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mset.h

#ifndef __SET_H__
#define __SET_H__

#include <mobject.h>

class AnySet : public Object {
};



//                                                                           //
//                     |   |           o                                     //
//                     |   |  ___         ___    _    |                      //
//                     |   |  ___| |/\ |  ___| |/ \  -+-                     //
//                      \ /  (   | |   | (   | |   |  |                      //
//                       V    \__| |   |  \__| |   |   \                     //
//                                                                           //

template <class ttype>
class Variant : public AnySet {
  public:
    ttype   i;

                            operator ttype  () const {return i;}
    //virtual DumpContext&  operator>>  (DumpContext& out) const {MUST_OVERLOAD}
};

template<class ttype>
class IteratorInterface {
  public:
    virtual void    start       ()=0;
    virtual void    next        ()=0;
    virtual bool    exhausted   () const=0;
    virtual bool    next_ends   () const {MUST_OVERLOAD}
};


//                                                                          //
//           -----                                                          //
//           |       _                ___       ___   |                     //
//           |---  |/ \  |   | |/|/| /   ) |/\  ___| -+-  __  |/\           //
//           |     |   | |   | | | | |---  |   (   |  |  /  \ |             //
//           |____ |   |  \__! | | |  \__  |    \__|   \ \__/ |             //
//                                                                          //


template <class ttype>
class Iterator : public Variant<ttype>, public IteratorInterface<ttype> {
    ttype   m_start, m_end, m_step;
  public:
    
                Iterator    (ttype s, ttype e=-9999, ttype stp=1) {
                    m_start = s;
                    ASSERTWITH (s<=e, "Start of a variant must be less than end");
                    m_end = (e==-9999)? s:e;
                    ASSERTWITH (stp>0, "Finite variant violation");
                    m_step = stp;
                    start ();
                }
    void        start       () {i = m_start;}
    void        next        () {i += m_step;}
    bool        exhausted   () const {return i>m_end;}
    bool        next_ends   () const {return i+m_step>m_end;}
    ttype       max         () const {return m_end;}
//  
//  OStream&    operator>>  (OStream& o) {
//      o.print ("{");
//      if (m_start != m_end)
//          ; else
//              o << i;
//      o.print ("}");
//  }
//  DumpContext&    operator>>  (DumpContext& out) const {
//      out.name ("m_start") << m_start;
//      out.name ("m_end") << m_end;
//      out.name ("m_step") << m_step;
//  }
//  
};

/*
template<class maintype, class subtype>
class Iterator {//: public IteratorInterface<Array<TYPE> > {
    //  mutable Array<TYPE>&    mArray;
    //Iterator<int>             mIter;
  public:
    Iterator    (const maintype& array) //:
//                      mArray (const_cast<Array<TYPE>&>(array)),
        //                      mIter(array.lower, array.upper, 1) {}
                {}
    void        start       () {}//mIter.start();}
    void        next        () {}//mIter.next();}
    bool        exhausted   () const {return false;}//mIter.exhausted();}
    //              operator const ttype& () const {return mArray[mIter.i];}
};
*/



//                                                                           //
//                ---                       o                                //
//                 |    _          ___         ___    _    |                 //
//                 |  |/ \  |   |  ___| |/\ |  ___| |/ \  -+-                //
//                 |  |   |  \ /  (   | |   | (   | |   |  |                 //
//                _|_ |   |   V    \__| |   |  \__| |   |   \                //
//                                                                           //

// A "variant" that does not change (i.e., a constant)
template <class ttype>
class Invariant : public Variant<ttype> {
  public:
                Invariant   (ttype s) {
                    i = s;
                }
    DumpContext&    operator>>  (DumpContext& out) const {
        out.name ("i") << i;
    }
};



#define forSet(name) for (name.start(); !name.exhausted(); name.next())

#endif

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