ginac/container.h

   1 /** @file container.h
   2  *
   3  *  Wrapper template for making GiNaC classes out of STL containers. */
   4
   5 /*
   6  *  GiNaC Copyright (C) 1999-2015 Johannes Gutenberg University Mainz, Germany
   7  *
   8  *  This program is free software; you can redistribute it and/or modify
   9  *  it under the terms of the GNU General Public License as published by
  10  *  the Free Software Foundation; either version 2 of the License, or
  11  *  (at your option) any later version.
  12  *
  13  *  This program is distributed in the hope that it will be useful,
  14  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  *  GNU General Public License for more details.
  17  *
  18  *  You should have received a copy of the GNU General Public License
  19  *  along with this program; if not, write to the Free Software
  20  *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
  21  */
  22
  23 #ifndef GINAC_CONTAINER_H
  24 #define GINAC_CONTAINER_H
  25
  26 #include "ex.h"
  27 #include "print.h"
  28 #include "archive.h"
  29 #include "assertion.h"
  30
  31 #include <algorithm>
  32 #include <iterator>
  33 #include <list>
  34 #include <memory>
  35 #include <stdexcept>
  36 #include <vector>
  37
  38 namespace GiNaC {
  39
  40 /** Helper template for encapsulating the reserve() mechanics of STL containers. */
  41 template <template <class T, class = std::allocator<T> > class C>
  42 class container_storage {
  43 protected:
  44         typedef C<ex> STLT;
  45
  46         container_storage() {}
  47         container_storage(size_t n, const ex & e) : seq(n, e) {}
  48
  49         template <class In>
  50         container_storage(In b, In e) : seq(b, e) {}
  51
  52         void reserve(size_t) {}
  53         static void reserve(STLT &, size_t) {}
  54
  55         STLT seq;
  56
  57         // disallow destruction of container through a container_storage*
  58 protected:
  59         ~container_storage() {}
  60 };
  61
  62 template <>
  63 inline void container_storage<std::vector>::reserve(size_t n) { seq.reserve(n); }
  64
  65 template <>
  66 inline void container_storage<std::vector>::reserve(std::vector<ex> & v, size_t n) { v.reserve(n); }
  67
  68
  69 /** Helper template to allow initialization of containers via an overloaded
  70  *  comma operator (idea stolen from Blitz++). */
  71 template <typename T, typename STLT>
  72 class container_init {
  73 public:
  74         container_init(STLT & s) : stlt(s) {}
  75
  76         container_init<T, STLT> operator,(const T & x)
  77         {
  78                 stlt.push_back(x);
  79                 return container_init<T, STLT>(stlt);
  80         }
  81
  82         // The following specializations produce much tighter code than the
  83         // general case above
  84
  85         container_init<T, STLT> operator,(int x)
  86         {
  87                 stlt.push_back(x);
  88                 return container_init<T, STLT>(stlt);
  89         }
  90
  91         container_init<T, STLT> operator,(unsigned int x)
  92         {
  93                 stlt.push_back(x);
  94                 return container_init<T, STLT>(stlt);
  95         }
  96
  97         container_init<T, STLT> operator,(long x)
  98         {
  99                 stlt.push_back(x);
 100                 return container_init<T, STLT>(stlt);
 101         }
 102
 103         container_init<T, STLT> operator,(unsigned long x)
 104         {
 105                 stlt.push_back(x);
 106                 return container_init<T, STLT>(stlt);
 107         }
 108
 109         container_init<T, STLT> operator,(double x)
 110         {
 111                 stlt.push_back(x);
 112                 return container_init<T, STLT>(stlt);
 113         }
 114
 115         container_init<T, STLT> operator,(const symbol & x)
 116         {
 117                 stlt.push_back(T(x));
 118                 return container_init<T, STLT>(stlt);
 119         }
 120
 121 private:
 122         container_init();
 123         STLT & stlt;
 124 };
 125
 126 /** Wrapper template for making GiNaC classes out of STL containers. */
 127 template <template <class T, class = std::allocator<T> > class C>
 128 class container : public basic, public container_storage<C> {
 129         GINAC_DECLARE_REGISTERED_CLASS(container, basic)
 130 protected:
 131         typedef typename container_storage<C>::STLT STLT;
 132
 133 public:
 134         typedef typename STLT::const_iterator const_iterator;
 135         typedef typename STLT::const_reverse_iterator const_reverse_iterator;
 136
 137 protected:
 138         // helpers
 139         static unsigned get_default_flags() { return 0; }
 140         static char get_open_delim() { return '('; }
 141         static char get_close_delim() { return ')'; }
 142
 143         // constructors
 144 public:
 145         container(STLT const & s, bool discardable = false)
 146         {
 147                 setflag(get_default_flags());
 148
 149                 if (discardable)
 150                         this->seq.swap(const_cast<STLT &>(s));
 151                 else
 152                         this->seq = s;
 153         }
 154
 155         explicit container(STLT && v)
 156         {
 157                 setflag(get_default_flags());
 158                 this->seq.swap(v);
 159         }
 160
 161         container(exvector::const_iterator b, exvector::const_iterator e)
 162          : container_storage<C>(b, e)
 163         {
 164                 setflag(get_default_flags());
 165         }
 166
 167         explicit container(const ex & p1)
 168          : container_storage<C>(1, p1)
 169         {
 170                 setflag(get_default_flags());
 171         }
 172
 173         container(const ex & p1, const ex & p2)
 174         {
 175                 setflag(get_default_flags());
 176                 this->reserve(this->seq, 2);
 177                 this->seq.push_back(p1); this->seq.push_back(p2);
 178         }
 179
 180         container(const ex & p1, const ex & p2, const ex & p3)
 181         {
 182                 setflag(get_default_flags());
 183                 this->reserve(this->seq, 3);
 184                 this->seq.push_back(p1); this->seq.push_back(p2); this->seq.push_back(p3);
 185         }
 186
 187         container(const ex & p1, const ex & p2, const ex & p3,
 188                   const ex & p4)
 189         {
 190                 setflag(get_default_flags());
 191                 this->reserve(this->seq, 4);
 192                 this->seq.push_back(p1); this->seq.push_back(p2); this->seq.push_back(p3);
 193                 this->seq.push_back(p4);
 194         }
 195
 196         container(const ex & p1, const ex & p2, const ex & p3,
 197                   const ex & p4, const ex & p5)
 198         {
 199                 setflag(get_default_flags());
 200                 this->reserve(this->seq, 5);
 201                 this->seq.push_back(p1); this->seq.push_back(p2); this->seq.push_back(p3);
 202                 this->seq.push_back(p4); this->seq.push_back(p5);
 203         }
 204
 205         container(const ex & p1, const ex & p2, const ex & p3,
 206                   const ex & p4, const ex & p5, const ex & p6)
 207         {
 208                 setflag(get_default_flags());
 209                 this->reserve(this->seq, 6);
 210                 this->seq.push_back(p1); this->seq.push_back(p2); this->seq.push_back(p3);
 211                 this->seq.push_back(p4); this->seq.push_back(p5); this->seq.push_back(p6);
 212         }
 213
 214         container(const ex & p1, const ex & p2, const ex & p3,
 215                   const ex & p4, const ex & p5, const ex & p6,
 216                   const ex & p7)
 217         {
 218                 setflag(get_default_flags());
 219                 this->reserve(this->seq, 7);
 220                 this->seq.push_back(p1); this->seq.push_back(p2); this->seq.push_back(p3);
 221                 this->seq.push_back(p4); this->seq.push_back(p5); this->seq.push_back(p6);
 222                 this->seq.push_back(p7);
 223         }
 224
 225         container(const ex & p1, const ex & p2, const ex & p3,
 226                   const ex & p4, const ex & p5, const ex & p6,
 227                   const ex & p7, const ex & p8)
 228         {
 229                 setflag(get_default_flags());
 230                 this->reserve(this->seq, 8);
 231                 this->seq.push_back(p1); this->seq.push_back(p2); this->seq.push_back(p3);
 232                 this->seq.push_back(p4); this->seq.push_back(p5); this->seq.push_back(p6);
 233                 this->seq.push_back(p7); this->seq.push_back(p8);
 234         }
 235
 236         container(const ex & p1, const ex & p2, const ex & p3,
 237                   const ex & p4, const ex & p5, const ex & p6,
 238                   const ex & p7, const ex & p8, const ex & p9)
 239         {
 240                 setflag(get_default_flags());
 241                 this->reserve(this->seq, 9);
 242                 this->seq.push_back(p1); this->seq.push_back(p2); this->seq.push_back(p3);
 243                 this->seq.push_back(p4); this->seq.push_back(p5); this->seq.push_back(p6);
 244                 this->seq.push_back(p7); this->seq.push_back(p8); this->seq.push_back(p9);
 245         }
 246
 247         container(const ex & p1, const ex & p2, const ex & p3,
 248                   const ex & p4, const ex & p5, const ex & p6,
 249                   const ex & p7, const ex & p8, const ex & p9,
 250                   const ex & p10)
 251         {
 252                 setflag(get_default_flags());
 253                 this->reserve(this->seq, 10);
 254                 this->seq.push_back(p1); this->seq.push_back(p2); this->seq.push_back(p3);
 255                 this->seq.push_back(p4); this->seq.push_back(p5); this->seq.push_back(p6);
 256                 this->seq.push_back(p7); this->seq.push_back(p8); this->seq.push_back(p9);
 257                 this->seq.push_back(p10);
 258         }
 259
 260         container(const ex & p1, const ex & p2, const ex & p3,
 261                   const ex & p4, const ex & p5, const ex & p6,
 262                   const ex & p7, const ex & p8, const ex & p9,
 263                   const ex & p10, const ex & p11)
 264         {
 265                 setflag(get_default_flags());
 266                 this->reserve(this->seq, 11);
 267                 this->seq.push_back(p1); this->seq.push_back(p2); this->seq.push_back(p3);
 268                 this->seq.push_back(p4); this->seq.push_back(p5); this->seq.push_back(p6);
 269                 this->seq.push_back(p7); this->seq.push_back(p8); this->seq.push_back(p9);
 270                 this->seq.push_back(p10); this->seq.push_back(p11);
 271         }
 272
 273         container(const ex & p1, const ex & p2, const ex & p3,
 274                   const ex & p4, const ex & p5, const ex & p6,
 275                   const ex & p7, const ex & p8, const ex & p9,
 276                   const ex & p10, const ex & p11, const ex & p12)
 277         {
 278                 setflag(get_default_flags());
 279                 this->reserve(this->seq, 12);
 280                 this->seq.push_back(p1); this->seq.push_back(p2); this->seq.push_back(p3);
 281                 this->seq.push_back(p4); this->seq.push_back(p5); this->seq.push_back(p6);
 282                 this->seq.push_back(p7); this->seq.push_back(p8); this->seq.push_back(p9);
 283                 this->seq.push_back(p10); this->seq.push_back(p11); this->seq.push_back(p12);
 284         }
 285
 286         container(const ex & p1, const ex & p2, const ex & p3,
 287                   const ex & p4, const ex & p5, const ex & p6,
 288                   const ex & p7, const ex & p8, const ex & p9,
 289                   const ex & p10, const ex & p11, const ex & p12,
 290                   const ex & p13)
 291         {
 292                 setflag(get_default_flags());
 293                 this->reserve(this->seq, 13);
 294                 this->seq.push_back(p1); this->seq.push_back(p2); this->seq.push_back(p3);
 295                 this->seq.push_back(p4); this->seq.push_back(p5); this->seq.push_back(p6);
 296                 this->seq.push_back(p7); this->seq.push_back(p8); this->seq.push_back(p9);
 297                 this->seq.push_back(p10); this->seq.push_back(p11); this->seq.push_back(p12);
 298                 this->seq.push_back(p13);
 299         }
 300
 301         container(const ex & p1, const ex & p2, const ex & p3,
 302                   const ex & p4, const ex & p5, const ex & p6,
 303                   const ex & p7, const ex & p8, const ex & p9,
 304                   const ex & p10, const ex & p11, const ex & p12,
 305                   const ex & p13, const ex & p14)
 306         {
 307                 setflag(get_default_flags());
 308                 this->reserve(this->seq, 14);
 309                 this->seq.push_back(p1); this->seq.push_back(p2); this->seq.push_back(p3);
 310                 this->seq.push_back(p4); this->seq.push_back(p5); this->seq.push_back(p6);
 311                 this->seq.push_back(p7); this->seq.push_back(p8); this->seq.push_back(p9);
 312                 this->seq.push_back(p10); this->seq.push_back(p11); this->seq.push_back(p12);
 313                 this->seq.push_back(p13); this->seq.push_back(p14);
 314         }
 315
 316         container(const ex & p1, const ex & p2, const ex & p3,
 317                   const ex & p4, const ex & p5, const ex & p6,
 318                   const ex & p7, const ex & p8, const ex & p9,
 319                   const ex & p10, const ex & p11, const ex & p12,
 320                   const ex & p13, const ex & p14, const ex & p15)
 321         {
 322                 setflag(get_default_flags());
 323                 this->reserve(this->seq, 15);
 324                 this->seq.push_back(p1); this->seq.push_back(p2); this->seq.push_back(p3);
 325                 this->seq.push_back(p4); this->seq.push_back(p5); this->seq.push_back(p6);
 326                 this->seq.push_back(p7); this->seq.push_back(p8); this->seq.push_back(p9);
 327                 this->seq.push_back(p10); this->seq.push_back(p11); this->seq.push_back(p12);
 328                 this->seq.push_back(p13); this->seq.push_back(p14); this->seq.push_back(p15);
 329         }
 330
 331         container(const ex & p1, const ex & p2, const ex & p3,
 332                   const ex & p4, const ex & p5, const ex & p6,
 333                   const ex & p7, const ex & p8, const ex & p9,
 334                   const ex & p10, const ex & p11, const ex & p12,
 335                   const ex & p13, const ex & p14, const ex & p15,
 336                   const ex & p16)
 337         {
 338                 setflag(get_default_flags());
 339                 this->reserve(this->seq, 16);
 340                 this->seq.push_back(p1); this->seq.push_back(p2); this->seq.push_back(p3);
 341                 this->seq.push_back(p4); this->seq.push_back(p5); this->seq.push_back(p6);
 342                 this->seq.push_back(p7); this->seq.push_back(p8); this->seq.push_back(p9);
 343                 this->seq.push_back(p10); this->seq.push_back(p11); this->seq.push_back(p12);
 344                 this->seq.push_back(p13); this->seq.push_back(p14); this->seq.push_back(p15);
 345                 this->seq.push_back(p16);
 346         }
 347
 348         // First step of initialization of container with a comma-separated
 349         // sequence of expressions. Subsequent steps are handled by
 350         // container_init<>::operator,().
 351         container_init<ex, STLT> operator=(const ex & x)
 352         {
 353                 this->seq.push_back(x);
 354                 return container_init<ex, STLT>(this->seq);
 355         }
 356
 357         // functions overriding virtual functions from base classes
 358 public:
 359         bool info(unsigned inf) const { return inherited::info(inf); }
 360         unsigned precedence() const { return 10; }
 361         size_t nops() const { return this->seq.size(); }
 362         ex op(size_t i) const;
 363         ex & let_op(size_t i);
 364         ex eval(int level = 0) const;
 365         ex subs(const exmap & m, unsigned options = 0) const;
 366
 367         void read_archive(const archive_node &n, lst &sym_lst)
 368         {
 369                 inherited::read_archive(n, sym_lst);
 370                 setflag(get_default_flags());
 371
 372                 archive_node::archive_node_cit first = n.find_first("seq");
 373                 archive_node::archive_node_cit last = n.find_last("seq");
 374                 ++last;
 375                 this->reserve(this->seq, last - first);
 376                 for (archive_node::archive_node_cit i=first; i<last; ++i) {
 377                         ex e;
 378                         n.find_ex_by_loc(i, e, sym_lst);
 379                         this->seq.push_back(e);
 380                 }
 381         }
 382
 383         /** Archive the object. */
 384         void archive(archive_node &n) const
 385         {
 386                 inherited::archive(n);
 387                 for (auto & i : this->seq) {
 388                         n.add_ex("seq", i);
 389                 }
 390         }
 391
 392 protected:
 393         ex conjugate() const
 394         {
 395                 STLT *newcont = nullptr;
 396                 for (const_iterator i=this->seq.begin(); i!=this->seq.end(); ++i) {
 397                         if (newcont) {
 398                                 newcont->push_back(i->conjugate());
 399                                 continue;
 400                         }
 401                         ex x = i->conjugate();
 402                         if (are_ex_trivially_equal(x, *i)) {
 403                                 continue;
 404                         }
 405                         newcont = new STLT;
 406                         this->reserve(*newcont, this->seq.size());
 407                         for (const_iterator j=this->seq.begin(); j!=i; ++j) {
 408                                 newcont->push_back(*j);
 409                         }
 410                         newcont->push_back(x);
 411                 }
 412                 if (newcont) {
 413                         ex result = thiscontainer(*newcont);
 414                         delete newcont;
 415                         return result;
 416                 }
 417                 return *this;
 418         }
 419
 420         ex real_part() const
 421         {
 422                 STLT cont;
 423                 this->reserve(cont, nops());
 424                 const_iterator b = begin();
 425                 const_iterator e = end();
 426                 for(const_iterator i=b; i!=e; ++i)
 427                         cont.push_back(i->real_part());
 428                 return thiscontainer(cont);
 429         }
 430
 431         ex imag_part() const
 432         {
 433                 STLT cont;
 434                 this->reserve(cont, nops());
 435                 const_iterator b = begin();
 436                 const_iterator e = end();
 437                 for(const_iterator i=b; i!=e; ++i)
 438                         cont.push_back(i->imag_part());
 439                 return thiscontainer(cont);
 440         }
 441
 442         bool is_equal_same_type(const basic & other) const;
 443
 444         // new virtual functions which can be overridden by derived classes
 445 protected:
 446         /** Similar to duplicate(), but with a preset sequence. Must be
 447          *  overridden by derived classes. */
 448         virtual ex thiscontainer(const STLT & v) const { return container(v); }
 449
 450         /** Similar to duplicate(), but with a preset sequence (which gets
 451          *  pilfered). Must be overridden by derived classes. */
 452         virtual ex thiscontainer(STLT && v) const { return container(std::move(v)); }
 453
 454         virtual void printseq(const print_context & c, char openbracket, char delim,
 455                               char closebracket, unsigned this_precedence,
 456                               unsigned upper_precedence = 0) const;
 457
 458         // non-virtual functions in this class
 459 private:
 460         void sort_(std::random_access_iterator_tag)
 461         {
 462                 std::sort(this->seq.begin(), this->seq.end(), ex_is_less());
 463         }
 464
 465         void sort_(std::input_iterator_tag)
 466         {
 467                 this->seq.sort(ex_is_less());
 468         }
 469
 470         void unique_()
 471         {
 472                 typename STLT::iterator p = std::unique(this->seq.begin(), this->seq.end(), ex_is_equal());
 473                 this->seq.erase(p, this->seq.end());
 474         }
 475
 476 public:
 477         container & prepend(const ex & b);
 478         container & append(const ex & b);
 479         container & remove_first();
 480         container & remove_last();
 481         container & remove_all();
 482         container & sort();
 483         container & unique();
 484
 485         const_iterator begin() const {return this->seq.begin();}
 486         const_iterator end() const {return this->seq.end();}
 487         const_reverse_iterator rbegin() const {return this->seq.rbegin();}
 488         const_reverse_iterator rend() const {return this->seq.rend();}
 489
 490 protected:
 491         void do_print(const print_context & c, unsigned level) const;
 492         void do_print_tree(const print_tree & c, unsigned level) const;
 493         void do_print_python(const print_python & c, unsigned level) const;
 494         void do_print_python_repr(const print_python_repr & c, unsigned level) const;
 495         STLT evalchildren(int level) const;
 496         STLT subschildren(const exmap & m, unsigned options = 0) const;
 497 };
 498
 499 /** Default constructor */
 500 template <template <class T, class = std::allocator<T> > class C>
 501 container<C>::container()
 502 {
 503         setflag(get_default_flags());
 504 }
 505
 506
 507 template <template <class T, class = std::allocator<T> > class C>
 508 void container<C>::do_print(const print_context & c, unsigned level) const
 509 {
 510         // always print brackets around seq, ignore upper_precedence
 511         printseq(c, get_open_delim(), ',', get_close_delim(), precedence(), precedence()+1);
 512 }
 513
 514 template <template <class T, class = std::allocator<T> > class C>
 515 void container<C>::do_print_tree(const print_tree & c, unsigned level) const
 516 {
 517         c.s << std::string(level, ' ') << class_name() << " @" << this
 518             << std::hex << ", hash=0x" << hashvalue << ", flags=0x" << flags << std::dec
 519             << ", nops=" << nops()
 520             << std::endl;
 521         const_iterator i = this->seq.begin(), end = this->seq.end();
 522         while (i != end) {
 523                 i->print(c, level + c.delta_indent);
 524                 ++i;
 525         }
 526         c.s << std::string(level + c.delta_indent,' ') << "=====" << std::endl;
 527 }
 528
 529 template <template <class T, class = std::allocator<T> > class C>
 530 void container<C>::do_print_python(const print_python & c, unsigned level) const
 531 {
 532         printseq(c, '[', ',', ']', precedence(), precedence()+1);
 533 }
 534
 535 template <template <class T, class = std::allocator<T> > class C>
 536 void container<C>::do_print_python_repr(const print_python_repr & c, unsigned level) const
 537 {
 538         c.s << class_name();
 539         printseq(c, '(', ',', ')', precedence(), precedence()+1);
 540 }
 541
 542 template <template <class T, class = std::allocator<T> > class C>
 543 ex container<C>::op(size_t i) const
 544 {
 545         GINAC_ASSERT(i < nops());
 546
 547         const_iterator it = this->seq.begin();
 548         advance(it, i);
 549         return *it;
 550 }
 551
 552 template <template <class T, class = std::allocator<T> > class C>
 553 ex & container<C>::let_op(size_t i)
 554 {
 555         GINAC_ASSERT(i < nops());
 556
 557         ensure_if_modifiable();
 558         typename STLT::iterator it = this->seq.begin();
 559         advance(it, i);
 560         return *it;
 561 }
 562
 563 template <template <class T, class = std::allocator<T> > class C>
 564 ex container<C>::eval(int level) const
 565 {
 566         if (level == 1)
 567                 return hold();
 568         else
 569                 return thiscontainer(evalchildren(level));
 570 }
 571
 572 template <template <class T, class = std::allocator<T> > class C>
 573 ex container<C>::subs(const exmap & m, unsigned options) const
 574 {
 575         // After having subs'ed all children, this method subs'es one final
 576         // level, but only if the intermediate result is a container! This is
 577         // because if the intermediate result has eval'ed to a non-container a
 578         // last level substitution would be wrong, as this example involving a
 579         // function f and its inverse f^-1 shows:
 580         // f(x).subs(x==f^-1(x))
 581         //   -> f(f^-1(x))  [subschildren]
 582         //   -> x           [eval]   /* must not subs(x==f^-1(x))! */
 583         STLT subsed = subschildren(m, options);
 584         if (!subsed.empty()) {
 585                 ex result(thiscontainer(subsed));
 586                 if (is_a<container<C> >(result))
 587                         return ex_to<basic>(result).subs_one_level(m, options);
 588                 else
 589                         return result;
 590         } else {
 591                 if (is_a<container<C> >(*this))
 592                         return subs_one_level(m, options);
 593                 else
 594                         return *this;
 595         }
 596 }
 597
 598 /** Compare two containers of the same type. */
 599 template <template <class T, class = std::allocator<T> > class C>
 600 int container<C>::compare_same_type(const basic & other) const
 601 {
 602         GINAC_ASSERT(is_a<container>(other));
 603         const container & o = static_cast<const container &>(other);
 604
 605         const_iterator it1 = this->seq.begin(), it1end = this->seq.end(),
 606                        it2 = o.seq.begin(), it2end = o.seq.end();
 607
 608         while (it1 != it1end && it2 != it2end) {
 609                 int cmpval = it1->compare(*it2);
 610                 if (cmpval)
 611                         return cmpval;
 612                 ++it1; ++it2;
 613         }
 614
 615         return (it1 == it1end) ? (it2 == it2end ? 0 : -1) : 1;
 616 }
 617
 618 template <template <class T, class = std::allocator<T> > class C>
 619 bool container<C>::is_equal_same_type(const basic & other) const
 620 {
 621         GINAC_ASSERT(is_a<container>(other));
 622         const container & o = static_cast<const container &>(other);
 623
 624         if (this->seq.size() != o.seq.size())
 625                 return false;
 626
 627         const_iterator it1 = this->seq.begin(), it1end = this->seq.end(), it2 = o.seq.begin();
 628         while (it1 != it1end) {
 629                 if (!it1->is_equal(*it2))
 630                         return false;
 631                 ++it1; ++it2;
 632         }
 633
 634         return true;
 635 }
 636
 637 /** Add element at front. */
 638 template <template <class T, class = std::allocator<T> > class C>
 639 container<C> & container<C>::prepend(const ex & b)
 640 {
 641         ensure_if_modifiable();
 642         this->seq.push_front(b);
 643         return *this;
 644 }
 645
 646 /** Add element at back. */
 647 template <template <class T, class = std::allocator<T> > class C>
 648 container<C> & container<C>::append(const ex & b)
 649 {
 650         ensure_if_modifiable();
 651         this->seq.push_back(b);
 652         return *this;
 653 }
 654
 655 /** Remove first element. */
 656 template <template <class T, class = std::allocator<T> > class C>
 657 container<C> & container<C>::remove_first()
 658 {
 659         ensure_if_modifiable();
 660         this->seq.pop_front();
 661         return *this;
 662 }
 663
 664 /** Remove last element. */
 665 template <template <class T, class = std::allocator<T> > class C>
 666 container<C> & container<C>::remove_last()
 667 {
 668         ensure_if_modifiable();
 669         this->seq.pop_back();
 670         return *this;
 671 }
 672
 673 /** Remove all elements. */
 674 template <template <class T, class = std::allocator<T> > class C>
 675 container<C> & container<C>::remove_all()
 676 {
 677         ensure_if_modifiable();
 678         this->seq.clear();
 679         return *this;
 680 }
 681
 682 /** Sort elements. */
 683 template <template <class T, class = std::allocator<T> > class C>
 684 container<C> & container<C>::sort()
 685 {
 686         ensure_if_modifiable();
 687         sort_(typename std::iterator_traits<typename STLT::iterator>::iterator_category());
 688         return *this;
 689 }
 690
 691 /** Specialization of container::unique_() for std::list. */
 692 template<> inline void container<std::list>::unique_()
 693 {
 694         this->seq.unique(ex_is_equal());
 695 }
 696
 697 /** Remove adjacent duplicate elements. */
 698 template <template <class T, class = std::allocator<T> > class C>
 699 container<C> & container<C>::unique()
 700 {
 701         ensure_if_modifiable();
 702         unique_();
 703         return *this;
 704 }
 705
 706 /** Print sequence of contained elements. */
 707 template <template <class T, class = std::allocator<T> > class C>
 708 void container<C>::printseq(const print_context & c, char openbracket, char delim,
 709                             char closebracket, unsigned this_precedence,
 710                             unsigned upper_precedence) const
 711 {
 712         if (this_precedence <= upper_precedence)
 713                 c.s << openbracket;
 714
 715         if (!this->seq.empty()) {
 716                 const_iterator it = this->seq.begin(), itend = this->seq.end();
 717                 --itend;
 718                 while (it != itend) {
 719                         it->print(c, this_precedence);
 720                         c.s << delim;
 721                         ++it;
 722                 }
 723                 it->print(c, this_precedence);
 724         }
 725
 726         if (this_precedence <= upper_precedence)
 727                 c.s << closebracket;
 728 }
 729
 730 template <template <class T, class = std::allocator<T> > class C>
 731 typename container<C>::STLT container<C>::evalchildren(int level) const
 732 {
 733         if (level == 1)
 734                 return this->seq;
 735         else if (level == -max_recursion_level)
 736                 throw std::runtime_error("max recursion level reached");
 737
 738         STLT s;
 739         this->reserve(s, this->seq.size());
 740
 741         --level;
 742         const_iterator it = this->seq.begin(), itend = this->seq.end();
 743         while (it != itend) {
 744                 s.push_back(it->eval(level));
 745                 ++it;
 746         }
 747
 748         return s;
 749 }
 750
 751 template <template <class T, class = std::allocator<T> > class C>
 752 typename container<C>::STLT container<C>::subschildren(const exmap & m, unsigned options) const
 753 {
 754         // returns an empty container if nothing had to be substituted
 755         // returns a STLT with substituted elements otherwise
 756
 757         const_iterator cit = this->seq.begin(), end = this->seq.end();
 758         while (cit != end) {
 759                 const ex & subsed_ex = cit->subs(m, options);
 760                 if (!are_ex_trivially_equal(*cit, subsed_ex)) {
 761
 762                         // copy first part of seq which hasn't changed
 763                         STLT s(this->seq.begin(), cit);
 764                         this->reserve(s, this->seq.size());
 765
 766                         // insert changed element
 767                         s.push_back(subsed_ex);
 768                         ++cit;
 769
 770                         // copy rest
 771                         while (cit != end) {
 772                                 s.push_back(cit->subs(m, options));
 773                                 ++cit;
 774                         }
 775
 776                         return s;
 777                 }
 778
 779                 ++cit;
 780         }
 781
 782         return STLT(); // nothing has changed
 783 }
 784
 785 } // namespace GiNaC
 786
 787 #endif // ndef GINAC_CONTAINER_H