lsys/util.h

/*
 * utilities...
 */

#ifndef UTIL_H
#define UTIL_H

#include <cmath>
#include <string>
#include <sstream>
#include <iostream>
#include <vector>
#include <exception>

using namespace std;

/* these defines belongs into config.h */
#define abstract = 0

#define t_no noexcept
#define t_err // can only throw error

inline bool equal (double a, double b)
{
  return abs (a - b) <= a * 1e-6;
}

template<typename T>
class shared;

template<typename T>
bool operator <(const shared<T> &a, const shared<T> &b) t_no;

template<typename T>
class shared {
        struct storage : T {
          int shared;
          
          storage () t_no : shared(0) {};
          storage (const storage &s) t_no : T(s), shared(0) {};
        };

protected:
        mutable storage *obj;

        void unshare() const t_no
          { if (obj->shared) { obj->shared--; obj = new storage(*obj); } };
        
public:
        typedef typename T::value_type      data_type;
        typedef typename T::const_iterator  const_iterator;
        typedef typename T::iterator        iterator;
        typedef typename T::const_reference const_reference;
        typedef typename T::reference       reference;
        typedef typename T::size_type       size_type;
        
        shared() t_no
          { obj = new storage; };
        
        shared(const shared<T> &v) t_no
          { obj = v.obj; obj->shared++; };
        
        shared<T> &operator =(const shared<T> &v) t_no
          {
            v.obj->shared++;
            if (obj->shared)
              obj->shared--;
            else
              delete obj;
            
            obj = v.obj;
            return *this;
          };
        
        ~shared() t_no
          { if (obj->shared) obj->shared--; else delete obj; };
        
        void erase () t_no
          {
            if (obj->shared)
              {
                obj->shared--;
                obj = new storage;
              }
            else
              obj->erase (obj->begin(), obj->end ());
          };
        
        const_iterator  begin () const t_no {             return obj->begin (); };
        const_iterator  end   () const t_no {             return obj->end   (); };
        iterator        begin ()       t_no { unshare (); return obj->begin (); };
        iterator        end   ()       t_no { unshare (); return obj->end   (); };
        size_type       size  () const t_no {             return obj->size  (); };
        bool            empty () const t_no {             return obj->empty (); };
        
        const T& operator ->() const t_no {             return *obj; };
        T&       operator ->()       t_no { unshare (); return *obj; };
        const T& operator * () const t_no {             return *obj; };
        T&       operator * ()       t_no { unshare (); return *obj; };
        operator const T&   () const t_no {             return *obj; };
        operator       T&   ()       t_no { unshare (); return *obj; };
        
        void insert (iterator a, iterator b, iterator c) t_no
          { unshare (); obj->insert (a, b, c); };
        
        friend bool operator < <>(const shared<T> &a, const shared<T> &b) t_no;
};

template<typename T>
bool operator <(const shared<T> &a, const shared<T> &b) t_no
{
  if (a.obj == b.obj)
    return false;
  else if (a.size () < b.size ())
    return true;
  else if (a.size () == b.size ())
    {
      typename shared<T>::const_iterator i, j;
      
      for (i = a.begin (), j = b.begin (); i != a.end (); ++i, ++j)
        if (*i < *j)
          return true;
    }
  
  return false;
}

template<typename T>
struct shared_vector : public shared< vector<T> > {
        T &operator [](int idx) t_no
          { shared< vector<T> >::unshare (); return shared< vector<T> >::obj->begin()+idx; };
        
        void push_back (typename shared_vector<T>::const_reference arg) t_no
          { shared< vector<T> >::unshare (); shared< vector<T> >::obj->push_back (arg); };
        
};

struct error : exception {
   string msg;

   const char *what () const t_no
     { return msg.c_str (); };
   
   error (const string &s) t_no : msg(s) {};
   error (const string &s, int line) t_no;
   error (const string &s, const class module &m) t_no;

   ~error () t_no
    { };
   
   template<typename T>
   error &operator <<(const T &s) t_no
     { msg.append (s); return *this; };
};

inline ostream &operator <<(ostream &o, const error &e) t_no
  { return o << e.what () << endl; }

#endif

Revision:	1.2
Committed:	Wed Nov 7 12:50:17 2018 UTC (7 years, 6 months ago) by root
Content type:	text/plain
Branch:	MAIN
CVS Tags:	HEAD
Changes since 1.1:	+3 -3 lines
Log Message:	* empty log message *
#	Content
1	/*
2	* utilities...
3	*/
4
5	#ifndef UTIL_H
6	#define UTIL_H
7
8	#include <cmath>
9	#include <string>
10	#include <sstream>
11	#include <iostream>
12	#include <vector>
13	#include <exception>
14
15	using namespace std;
16
17	/* these defines belongs into config.h */
18	#define abstract = 0
19
20	#define t_no noexcept
21	#define t_err // can only throw error
22
23	inline bool equal (double a, double b)
24	{
25	return abs (a - b) <= a * 1e-6;
26	}
27
28	template<typename T>
29	class shared;
30
31	template<typename T>
32	bool operator <(const shared<T> &a, const shared<T> &b) t_no;
33
34	template<typename T>
35	class shared {
36	struct storage : T {
37	int shared;
38
39	storage () t_no : shared(0) {};
40	storage (const storage &s) t_no : T(s), shared(0) {};
41	};
42
43	protected:
44	mutable storage *obj;
45
46	void unshare() const t_no
47	{ if (obj->shared) { obj->shared--; obj = new storage(*obj); } };
48
49	public:
50	typedef typename T::value_type data_type;
51	typedef typename T::const_iterator const_iterator;
52	typedef typename T::iterator iterator;
53	typedef typename T::const_reference const_reference;
54	typedef typename T::reference reference;
55	typedef typename T::size_type size_type;
56
57	shared() t_no
58	{ obj = new storage; };
59
60	shared(const shared<T> &v) t_no
61	{ obj = v.obj; obj->shared++; };
62
63	shared<T> &operator =(const shared<T> &v) t_no
64	{
65	v.obj->shared++;
66	if (obj->shared)
67	obj->shared--;
68	else
69	delete obj;
70
71	obj = v.obj;
72	return *this;
73	};
74
75	~shared() t_no
76	{ if (obj->shared) obj->shared--; else delete obj; };
77
78	void erase () t_no
79	{
80	if (obj->shared)
81	{
82	obj->shared--;
83	obj = new storage;
84	}
85	else
86	obj->erase (obj->begin(), obj->end ());
87	};
88
89	const_iterator begin () const t_no { return obj->begin (); };
90	const_iterator end () const t_no { return obj->end (); };
91	iterator begin () t_no { unshare (); return obj->begin (); };
92	iterator end () t_no { unshare (); return obj->end (); };
93	size_type size () const t_no { return obj->size (); };
94	bool empty () const t_no { return obj->empty (); };
95
96	const T& operator ->() const t_no { return *obj; };
97	T& operator ->() t_no { unshare (); return *obj; };
98	const T& operator * () const t_no { return *obj; };
99	T& operator * () t_no { unshare (); return *obj; };
100	operator const T& () const t_no { return *obj; };
101	operator T& () t_no { unshare (); return *obj; };
102
103	void insert (iterator a, iterator b, iterator c) t_no
104	{ unshare (); obj->insert (a, b, c); };
105
106	friend bool operator < <>(const shared<T> &a, const shared<T> &b) t_no;
107	};
108
109	template<typename T>
110	bool operator <(const shared<T> &a, const shared<T> &b) t_no
111	{
112	if (a.obj == b.obj)
113	return false;
114	else if (a.size () < b.size ())
115	return true;
116	else if (a.size () == b.size ())
117	{
118	typename shared<T>::const_iterator i, j;
119
120	for (i = a.begin (), j = b.begin (); i != a.end (); ++i, ++j)
121	if (i < j)
122	return true;
123	}
124
125	return false;
126	}
127
128	template<typename T>
129	struct shared_vector : public shared< vector<T> > {
130	T &operator [](int idx) t_no
131	{ shared< vector<T> >::unshare (); return shared< vector<T> >::obj->begin()+idx; };
132
133	void push_back (typename shared_vector<T>::const_reference arg) t_no
134	{ shared< vector<T> >::unshare (); shared< vector<T> >::obj->push_back (arg); };
135
136	};
137
138	struct error : exception {
139	string msg;
140
141	const char *what () const t_no
142	{ return msg.c_str (); };
143
144	error (const string &s) t_no : msg(s) {};
145	error (const string &s, int line) t_no;
146	error (const string &s, const class module &m) t_no;
147
148	~error () t_no
149	{ };
150
151	template<typename T>
152	error &operator <<(const T &s) t_no
153	{ msg.append (s); return *this; };
154	};
155
156	inline ostream &operator <<(ostream &o, const error &e) t_no
157	{ return o << e.what () << endl; }
158
159	#endif
160