parser.c

   1 #include <malloc.h>
   2 #include <math.h>
   3 #include <stdio.h>
   4 #include <stdlib.h>
   5 #include <string.h>
   6
   7 #include "debug.h"
   8
   9 #include "parser.h"
  10
  11 /* global variables */
  12
  13 double answer = 0;
  14
  15 #define DEFAULT_STORAGE_SIZE 10
  16 int storage_size = -1;
  17 double *storage = NULL;
  18
  19 int argument_size = 0;
  20 double *argument = NULL;
  21
  22 int stack_size = 0;
  23 double *stack = NULL;
  24
  25 #define DEFAULT_FORMAT "=> %.6g\n"
  26 char *format = NULL;
  27 char *minform = NULL;
  28
  29 workspace_t *programs = NULL;
  30 int nb_programs = 0;
  31
  32 /* compare codes */
  33
  34 int codecmp (char *ref, char *str)
  35 {
  36     int sig;
  37
  38     while (*ref != '\0') {
  39         if (*ref == '\t') {
  40              sig = (*str == '.') ? -1 : ((*str >= '0') && (*str <= '9'));
  41         } else {
  42             sig = *str - *ref;
  43         }
  44         if (sig != 0) {
  45             return (sig > 0) ? 1 : -1;
  46         }
  47         str++;
  48         ref++;
  49     }
  50
  51     return 0;
  52 }
  53
  54 /* calloc or die function */
  55
  56 void *callocordie (size_t count, size_t size)
  57 {
  58     if (count * size == 0) {
  59         return NULL;
  60     }
  61     void *new = calloc (count, size);
  62     if (new == NULL) {
  63         VERBOSE (ERROR, fprintf (stderr, "can't allocate memory\n"));
  64         exit (1);
  65     }
  66     return new;
  67 }
  68
  69 /* allocate new element */
  70
  71 element_t *newelement (func_t function, int nbops, int prio)
  72 {
  73     element_t *new = (element_t *) callocordie (1, sizeof (element_t));
  74     if (nbops) {
  75         new->ops = (element_t **) callocordie (nbops, sizeof (element_t *));
  76     }
  77     new->func = function;
  78     new->nbops = nbops;
  79     new->prio = prio;
  80
  81     return new;
  82 }
  83
  84 /* desallocate element */
  85
  86 void delelement (element_t *root)
  87 {
  88     if ((root != NULL) && (root != ERROR_OP)) {
  89         int i;
  90         for (i = 0; i < root->nbops; i++) {
  91             delelement (root->ops[i]);
  92         }
  93         if (root->nbops) {
  94             free (root->ops);
  95         }
  96         free (root);
  97     }
  98 }
  99
 100 /* duplicate element */
 101
 102 element_t *dupelement (element_t *root)
 103 {
 104     element_t *tmp = NULL;
 105     int i;
 106
 107     if ((root == NULL) || (root == ERROR_OP)) {
 108         return root;
 109     }
 110     tmp = newelement (root->func, root->nbops, root->prio);
 111     tmp->value = root->value;
 112     for (i = 0; i < root->nbops; i++) {
 113         tmp->ops[i] = dupelement (root->ops[i]);
 114     }
 115     return tmp;
 116 }
 117
 118 /* functions */
 119
 120 #define MAX_ARGS 100
 121
 122 #define NB_OPERATORS 14
 123 keyword_t operators[NB_OPERATORS] = {
 124     { "+\t", Add, 2, 1, 1},
 125     { "-\t", Sub, 2, 1, 1},
 126     { "*",   Mul, 2, 1, 2},
 127     { "/",   Div, 2, 1, 2},
 128     { "%",   Mod, 2, 1, 3},
 129     { "^",   Pow, 2, 1, 4},
 130     { "==",  Equal, 2, 2, -1},
 131     { "!=",  Diff, 2, 2, -1},
 132     { ">=",  Ge, 2, 2, -1},
 133     { "<=",  Le, 2, 2, -1},
 134     { ">",   Gt, 2, 1, -1},
 135     { "<",   Lt, 2, 1, -1},
 136     { "&",   And, 2, 1, -2},
 137     { "|",   Or, 2, 1, -2}
 138 };
 139
 140 #define NB_FUNCTIONS 50
 141 keyword_t functions[NB_FUNCTIONS] = {
 142     { "sqrt", Sqr, 1, 4, 5},
 143     { "pow",  Pow, 2, 3, 5},
 144     { "cos",  Cos, 1, 3, 5},
 145     { "sin",  Sin, 1, 3, 5},
 146     { "tan",  Tan, 1, 3, 5},
 147     { "acos", Acos, 1, 4, 5},
 148     { "asin", Asin, 1, 4, 5},
 149     { "atan", Atan, 1, 4, 5},
 150     { "ln",   Ln, 1, 2, 5},
 151     { "log",  Log, 1, 3, 5},
 152     { "exp",  Exp, 1, 3, 5},
 153     { "erfc", Erfc, 1, 4, 5},
 154     { "erf",  Erf, 1, 3, 5},
 155     { "abs",  Abs, 1, 3, 5},
 156     { "floor", Floor, 1, 5, 5},
 157     { "ceil", Ceil, 1, 4, 5},
 158     { "sto",  Store, 2, 3, 5},
 159     { "rcl",  Recall, 1, 3, 5},
 160     { "inc",  Inc, 1, 3, 5},
 161     { "dec",  Dec, 1, 3, 5},
 162     { "disp", Disp, 0, 4, 9},
 163     { "mem",  Mem, 1, 3, 5},
 164     { "clr",  Clear, 0, 3, 9},
 165     { "quit", Quit, 0, 4, 9},
 166     { "help", Help, 0, 4, 9},
 167     { "!",    Not, 1, 1, 6},
 168     { "cond", Cond, 3, 4, 5},
 169     { "while", While, 2, 5, 5},
 170     { "print", Print, 1, 5, 5},
 171     { "prog", Prog, 2, 4, 9},
 172     { "arg",  Arg, 1, 3, 5},
 173     { "call", Call, MAX_ARGS, 4, 5},
 174     { "ls",   List, 0, 2, 9},
 175     { "edit", Edit, 1, 4, 9},
 176     { "del",  Del, 1, 3, 9},
 177     { "get",  Get, 1, 3, 5},
 178     { "len",  Length, 0, 3, 5},
 179     { "pop",  Pop, 0, 3, 5},
 180     { "push", Push, 1, 4, 5},
 181     { "put",  Put, 2, 3, 5},
 182     { "set",  Set, MAX_ARGS, 3, 5},
 183     { "show", Show, 0, 4, 5},
 184     { "max",  Max, 2, 3, 5},
 185     { "mean", Mean, 2, 4, 5},
 186     { "med",  Median, 0, 3, 5},
 187     { "min",  Min, 2, 3, 5},
 188     { "ord",  Order, 0, 3, 5},
 189     { "prod", Prod, 0, 4, 5},
 190     { "sum",  Sum, 0, 3, 5},
 191     { "var",  Variance, 2, 3, 5},
 192 };
 193
 194 #define NB_CONSTANTS 3
 195 keyword_t constants[NB_CONSTANTS] = {
 196     { "ans", Ans, 0, 3, 5},
 197     { "e",   E, 0, 1, 5},
 198     { "pi",  Pi, 0, 2, 5}
 199 };
 200
 201 #define NB_SYMBOLS 4
 202 char *symbols[NB_SYMBOLS] = {
 203     "(", ")", "{", "}"
 204 };
 205
 206 /* subparser function */
 207
 208 element_t *subparser (element_t **proot, char **pstr, func_t func, int nbops, int prio)
 209 {
 210     element_t *new = newelement (func, nbops, prio);
 211     new->ops[0] = *proot;
 212     new->ops[1] = parser (*pstr, pstr, new->prio);
 213     if ((new->ops[1] == NULL) || ((new->ops[1] != ERROR_OP) && (new->ops[1]->prio == 9))) {
 214         delelement (new->ops[1]);
 215         new->ops[1] = ERROR_OP;
 216     }
 217     if (new->ops[1] == ERROR_OP) {
 218         delelement (new);
 219         *proot = NULL;
 220         return ERROR_OP;
 221     }
 222     *proot = newelement (Val, 1, 5);
 223     (*proot)->ops[0] = new;
 224
 225     return *proot;
 226 }
 227
 228 /* parser function */
 229
 230 element_t *parser (char *str, char **next, int prio)
 231 {
 232     element_t *root = NULL;
 233     char *string = str;
 234     int i;
 235
 236     VERBOSE (DEBUG, fprintf (stdout, "Starting parsing\n"));
 237
 238     /* main loop */
 239     while (*str != '\0') {
 240         int found = 0;
 241         element_t *new = NULL;
 242         VERBOSE (INFO, fprintf (stdout, "Processing: %s\n", str));
 243
 244         /* end without printing */
 245
 246         if (*str == ';') {
 247             if (root) {
 248                 root->hidden = 1;
 249             }
 250             break;
 251         }
 252
 253         /* skip spaces and tabs */
 254
 255         if ((*str == ' ') || (*str == '\t')) {
 256             str++;
 257             continue;
 258         }
 259
 260         /* check for open brace */
 261
 262         if (*str == '{') {
 263             VERBOSE (DEBUG, fprintf (stdout, "start processing brace\n"));
 264             if (root != NULL) {
 265                 delelement (root);
 266                 return ERROR_OP;
 267             }
 268             root = newelement (Code, 0, 5);
 269
 270             do {
 271                 new = parser (str + 1, &str, 0);
 272                 if ((new == NULL) || ((new != ERROR_OP) && (new->prio == 9))) {
 273                     delelement (new);
 274                     new = ERROR_OP;
 275                 }
 276                 if (new == ERROR_OP) {
 277                     delelement (root);
 278                     return ERROR_OP;
 279                 }
 280                 element_t *newcode = newelement (Code, root->nbops + 1, 5);
 281                 for (i = 0; i < root->nbops; i++) {
 282                     newcode->ops[i] = root->ops[i];
 283                     root->ops[i] = NULL;
 284                 }
 285                 newcode->ops[root->nbops] = new;
 286                 delelement (root);
 287                 root = newcode;
 288             } while (*str == ',');
 289
 290             if (*str != '}') {
 291                 delelement (root);
 292                 return ERROR_OP;
 293             }
 294             str++;
 295             VERBOSE (DEBUG, fprintf (stdout, "stop processing brace\n"));
 296             continue;
 297         }
 298
 299         /* check for open bracket */
 300
 301         if (*str == '(') {
 302             VERBOSE (DEBUG, fprintf (stdout, "start processing bracket\n"));
 303             if (root) {
 304                 do {
 305                     found = 0;
 306                     new = parser (str + 1, &str, 0);
 307                     if ((new == NULL) || ((new != ERROR_OP) && (new->prio == 9))) {
 308                         delelement (new);
 309                         new = ERROR_OP;
 310                     }
 311                     if ((new == NULL) || (new == ERROR_OP)) {
 312                         delelement (root);
 313                         return ERROR_OP;
 314                     }
 315                     for (i = 0; i < root->nbops; i++) {
 316                         if (root->ops[i] == NULL) {
 317                             root->ops[i] = new;
 318                             found = 1;
 319                             break;
 320                         }
 321                     }
 322                     if (!found) {
 323                         delelement (new);
 324                         delelement (root);
 325                         return ERROR_OP;
 326                     }
 327                 } while (*str == ',');
 328             } else {
 329                 root = newelement (Val, 1, 5);
 330                 new = parser (str + 1, &str, 0);
 331                 if ((new == NULL) || ((new != ERROR_OP) && (new->prio == 9))) {
 332                     delelement (new);
 333                     new = ERROR_OP;
 334                 }
 335                 if ((new == NULL) || (new == ERROR_OP) || (*str == ',')) {
 336                     delelement (new);
 337                     delelement (root);
 338                     return ERROR_OP;
 339                 }
 340                 root->ops[0] = new;
 341             }
 342             if (*str != ')') {
 343                 delelement (root);
 344                 return ERROR_OP;
 345             }
 346             str++;
 347             VERBOSE (DEBUG, fprintf (stdout, "stop processing bracket\n"));
 348             continue;
 349         }
 350
 351         /* check for closing bracket, closing brace or koma */
 352
 353         if ((*str == ')') || (*str == '}') || (*str == ',')) {
 354             if (prio == -9) {
 355                 delelement (root);
 356                 return ERROR_OP;
 357             }
 358             if (next != NULL) {
 359                 *next = str;
 360             }
 361             return root;
 362         }
 363
 364         /* look for operators */
 365
 366         for (i = 0; i < NB_OPERATORS; i++) {
 367             keyword_t *operator = operators + i;
 368             if (codecmp (operator->keyword, str) == 0) {
 369                 VERBOSE (DEBUG, fprintf (stdout, "start processing operator\n"));
 370                 if ((root) && (root->prio == 9)) {
 371                     VERBOSE (DEBUG, fprintf (stdout, "terminal function (%d)\n", root->func));
 372                     delelement (root);
 373                     return ERROR_OP;
 374                 } else if (root) {
 375                     if ((prio) && (prio > operator->prio)) {
 376                         VERBOSE (DEBUG, fprintf (stdout, "stop because operator priority\n"));
 377                         *next = str;
 378                         return root;
 379                     }
 380                     str += operator->offset;
 381                     VERBOSE (INFO, fprintf (stdout, "Oper: %d\n", operator->func));
 382                     if (subparser (&root, &str, operator->func, operator->nbops, operator->prio) == ERROR_OP) {
 383                         delelement (root);
 384                         return ERROR_OP;
 385                     }
 386                 } else if (*str == '-') {
 387                     root = newelement (Sig, 1, 6);
 388                 } else {
 389                     return ERROR_OP;
 390                 }
 391                 found = 1;
 392                 VERBOSE (DEBUG, fprintf (stdout, "stop processing operator\n"));
 393                 break;
 394             }
 395         }
 396         if (found) {
 397             continue;
 398         }
 399
 400         /* look for functions */
 401
 402         for (i = 0; i < NB_FUNCTIONS; i++) {
 403             keyword_t *function = functions + i;
 404             if (codecmp (function->keyword, str) == 0) {
 405                 VERBOSE (DEBUG, fprintf (stdout, "start processing function\n"));
 406                 if (root == NULL) {
 407                     VERBOSE (INFO, fprintf (stdout, "Func: %d\n", function->func));
 408                     root = newelement (function->func, function->nbops, function->prio);
 409                 } else {
 410                     delelement (root);
 411                     return ERROR_OP;
 412                 }
 413                 str += function->offset;
 414                 found = 1;
 415                 VERBOSE (DEBUG, fprintf (stdout, "stop processing function\n"));
 416                 break;
 417             }
 418         }
 419         if (found) {
 420             continue;
 421         }
 422
 423         /* look for constant */
 424
 425         for (i = 0; i < NB_CONSTANTS; i++) {
 426             keyword_t *constant = constants + i;
 427             if (codecmp (constant->keyword, str) == 0) {
 428                 VERBOSE (DEBUG, fprintf (stdout, "start processing constant\n"));
 429                 if (root == NULL) {
 430                     VERBOSE (INFO, fprintf (stdout, "Const: %d\n", constant->func));
 431                     root = newelement (constant->func, constant->nbops, constant->prio);
 432                 } else {
 433                     delelement (root);
 434                     return ERROR_OP;
 435                 }
 436                 str += constant->offset;
 437                 found = 1;
 438                 VERBOSE (DEBUG, fprintf (stdout, "stop processing constant\n"));
 439                 break;
 440             }
 441         }
 442         if (found) {
 443             continue;
 444         }
 445
 446         /* look for number */
 447
 448         if (((*str >= '0') && (*str <= '9')) ||
 449             (*str == '.') || (*str == '+') || (*str == '-')) {
 450             VERBOSE (DEBUG, fprintf (stdout, "start processing value\n"));
 451             char *pt;
 452             double value = strtod (str, &pt);
 453             VERBOSE (INFO, fprintf (stdout, "Value: %f\n", value));
 454             if (str != pt) {
 455                 if ((root == NULL) || (root->prio == 6)) {
 456                     new = newelement (Val, 1, 5);
 457                     new->value = value;
 458                     if (root == NULL) {
 459                         root = new;
 460                     } else {
 461                         for (i = 0; i < root->nbops; i++) {
 462                             if (root->ops[i] == NULL) {
 463                                 root->ops[i] = new;
 464                                 found = 1;
 465                                 break;
 466                             }
 467                         }
 468                         if (!found) {
 469                             delelement (new);
 470                             delelement (root);
 471                             return ERROR_OP;
 472                         }
 473                     }
 474                     str = pt;
 475                 } else if ((*str == '+') || (*str == '-')) {
 476                     if ((prio) && (prio > 1)) {
 477                         VERBOSE (DEBUG, fprintf (stdout, "stop because operator priority\n"));
 478                         *next = str;
 479                         return root;
 480                     }
 481                     if (subparser (&root, &str, Add, 2, 1) == ERROR_OP) {
 482                         delelement (root);
 483                         return ERROR_OP;
 484                     }
 485                 } else {
 486                     delelement (root);
 487                     return ERROR_OP;
 488                 }
 489                 found = 1;
 490             }
 491             VERBOSE (DEBUG, fprintf (stdout, "stop processing value\n"));
 492         }
 493
 494         /* error */
 495
 496         if (!found) {
 497             delelement (root);
 498             return ERROR_OP;
 499         }
 500
 501     }
 502
 503     if (next != NULL) {
 504         *next = str;
 505     }
 506
 507     /* save string */
 508     if (root != NULL) {
 509         root->string = string;
 510     }
 511
 512     return root;
 513 }
 514
 515 /* print element tree */
 516
 517 void print_element (element_t *root, int level)
 518 {
 519     char *func = NULL;
 520     int i;
 521
 522     if ((root == NULL) || (root == ERROR_OP)) {
 523         return;
 524     }
 525
 526     for (i = 0; i < level; i++) {
 527         fprintf (stdout, " ");
 528     }
 529
 530     switch (root->func) {
 531     case Val: func = "Value"; break;
 532     case Sig: func = "Sign"; break;
 533     case Add: func = "Addition"; break;
 534     case Sub: func = "Subtraction"; break;
 535     case Mul: func = "Multiplication"; break;
 536     case Div: func = "Division"; break;
 537     case Mod: func = "Modulo"; break;
 538     case Pow: func = "Power"; break;
 539     case Sqr: func = "Square Root"; break;
 540     case Cos: func = "Cosine"; break;
 541     case Sin: func = "Sine"; break;
 542     case Tan: func = "Tangent"; break;
 543     case Acos: func = "Arc Cosine"; break;
 544     case Asin: func = "Arc Sine"; break;
 545     case Atan: func = "Arc Tangent"; break;
 546     case Ln: func = "Logarithm (natural)"; break;
 547     case Log: func = "Logarithm (10 base)"; break;
 548     case Exp: func = "Exponantial"; break;
 549     case Erfc: func = "Complementary Error Function"; break;
 550     case Erf: func = "Error Function"; break;
 551     case Abs: func = "Absolute value"; break;
 552     case Ceil: func = "Ceil value"; break;
 553     case Floor: func = "Floor value"; break;
 554     case Store: func = "Store"; break;
 555     case Recall: func = "Recall"; break;
 556     case Inc: func = "Increase"; break;
 557     case Dec: func = "Decrease"; break;
 558     case Disp: func = "Display"; break;
 559     case Mem: func = "Memory"; break;
 560     case Clear: func = "Clear"; break;
 561     case Quit: func = "Quit"; break;
 562     case Help: func = "Help"; break;
 563     case Ans: func = "Ans"; break;
 564     case Pi: func = "Pi"; break;
 565     case E: func = "E"; break;
 566     case Equal: func = "Equal"; break;
 567     case Diff: func = "Different"; break;
 568     case Ge: func = "Greater or equal"; break;
 569     case Le: func = "Lesser or equal"; break;
 570     case Gt: func = "Greater"; break;
 571     case Lt: func = "Lesser"; break;
 572     case And: func = "And"; break;
 573     case Or: func = "Or"; break;
 574     case Not: func = "Not"; break;
 575     case Cond: func = "Condition"; break;
 576     case While: func = "While"; break;
 577     case Code: func = "Code"; break;
 578     case Print: func = "Print"; break;
 579     case Prog: func = "Program"; break;
 580     case Arg: func = "Argument"; break;
 581     case Call: func = "Call"; break;
 582     case List: func = "List"; break;
 583     case Edit: func = "Edit"; break;
 584     case Del: func = "Del"; break;
 585     case Get: func = "Get"; break;
 586     case Length: func = "Length"; break;
 587     case Pop: func = "Pop"; break;
 588     case Push: func = "Push"; break;
 589     case Put: func = "Put"; break;
 590     case Set: func = "Set"; break;
 591     case Show: func = "Show"; break;
 592     case Max: func = "Maximum"; break;
 593     case Mean: func = "Mean"; break;
 594     case Median: func = "Median"; break;
 595     case Min: func = "Minimum"; break;
 596     case Order: func = "Order"; break;
 597     case Prod: func = "Product"; break;
 598     case Sum: func = "Sum"; break;
 599     case Variance: func = "Variance"; break;
 600     }
 601
 602     fprintf (stdout, "Function: %s\n", func);
 603
 604     if ((root->func == Val) && (root->ops[0] == NULL)) {
 605         for (i = 0; i < level; i++) {
 606             fprintf (stdout, " ");
 607         }
 608         fprintf (stdout, "value: %f\n", root->value);
 609     } else {
 610         for (i = 0; i < root->nbops; i++) {
 611             print_element (root->ops[i], level + 1);
 612         }
 613     }
 614 }
 615
 616 /* storage functions */
 617
 618 void memory (int nb)
 619 {
 620     int i, l;
 621     double *tmp = NULL;
 622     if (nb != storage_size) {
 623         l = (nb < storage_size) ? nb : storage_size;
 624         tmp = (double *) callocordie (nb, sizeof (double));
 625         for (i = 0; i < l; i++) {
 626             tmp[i] = storage[i];
 627         }
 628         if (storage != NULL) {
 629             free (storage);
 630         }
 631         storage = tmp;
 632         storage_size = nb;
 633     }
 634 }
 635
 636 double store (int index, double value)
 637 {
 638     if (storage_size == -1) {
 639         memory (DEFAULT_STORAGE_SIZE);
 640     }
 641     if ((index > 0) && (index <= storage_size)) {
 642         storage[index - 1] = value;
 643     } else {
 644         VERBOSE (WARNING, fprintf (stdout, "invalid index (%d) [%d, %d]\n", index, (storage_size) ? 1 : 0, storage_size));
 645     }
 646     return value;
 647 }
 648
 649 double recall (int index)
 650 {
 651     if (storage_size == -1) {
 652         memory (DEFAULT_STORAGE_SIZE);
 653     }
 654     if ((index > 0) && (index <= storage_size)) {
 655         return storage[index - 1];
 656     } else {
 657         VERBOSE (WARNING, fprintf (stdout, "invalid index (%d) [%d, %d]\n", index, (storage_size) ? 1 : 0, storage_size));
 658     }
 659     return 0;
 660 }
 661
 662 double increase (int index)
 663 {
 664     if (storage_size == -1) {
 665         memory (DEFAULT_STORAGE_SIZE);
 666     }
 667     if ((index > 0) && (index <= storage_size)) {
 668         return storage[index - 1]++;
 669     } else {
 670         VERBOSE (WARNING, fprintf (stdout, "invalid index (%d) [%d, %d]\n", index, (storage_size) ? 1 : 0, storage_size));
 671     }
 672     return 0;
 673 }
 674
 675 double decrease (int index)
 676 {
 677     if (storage_size == -1) {
 678         memory (DEFAULT_STORAGE_SIZE);
 679     }
 680     if ((index > 0) && (index <= storage_size)) {
 681         return storage[index - 1]--;
 682     } else {
 683         VERBOSE (WARNING, fprintf (stdout, "invalid index (%d) [%d, %d]\n", index, (storage_size) ? 1 : 0, storage_size));
 684     }
 685     return 0;
 686 }
 687
 688 void display (void)
 689 {
 690     int i;
 691     if (storage_size == -1) {
 692         memory (DEFAULT_STORAGE_SIZE);
 693     }
 694     fprintf (stdout, "storage:");
 695     for (i = 0; i < storage_size; i++) {
 696         fprintf (stdout, " ");
 697         fprintf (stdout, minform, storage[i]);
 698     }
 699     fprintf (stdout, "\n");
 700 }
 701
 702 void clear ()
 703 {
 704     int i;
 705     for (i = 0; i < storage_size; i++) {
 706         storage[i] = 0;
 707     }
 708 }
 709
 710 /* While do function */
 711
 712 double while_do (element_t *cond, element_t *action)
 713 {
 714     double ret = 0;
 715     element_t *temp = NULL;
 716
 717     VERBOSE (DEBUG, fprintf (stdout, "starting while loop\n"));
 718     while (1) {
 719         VERBOSE (DEBUG, fprintf (stdout, "loop...\n"));
 720
 721         temp = dupelement (cond);
 722         double test = evaluate_element (temp, 0);
 723         delelement (temp);
 724         if (!test) {
 725             break;
 726         }
 727         if (action) {
 728             temp = dupelement (action);
 729             ret = evaluate_element (temp, 0);
 730             delelement (temp);
 731         }
 732     }
 733
 734     VERBOSE (DEBUG, fprintf (stdout, "ending while loop\n"));
 735
 736     return ret;
 737 }
 738
 739 /* program function */
 740
 741 double execute_code (element_t **prog, int nbcalls)
 742 {
 743     double ret = 0;
 744     int i;
 745     for (i = 0; i < nbcalls; i++) {
 746         ret = evaluate_element (prog[i], 0);
 747     }
 748     return ret;
 749 }
 750
 751 /* print function */
 752
 753 void set_format (char *prompt, int precision)
 754 {
 755     char buffer[128] = {0};
 756     free_format ();
 757     sprintf (buffer, "%s%%.%dg\n", prompt, precision);
 758     format = strdup (buffer);
 759     sprintf (buffer, "%%.%dg", precision);
 760     minform = strdup (buffer);
 761 }
 762
 763 void free_format ()
 764 {
 765     if (format) {
 766         free (format);
 767         format = NULL;
 768     }
 769     if (minform) {
 770         free (minform);
 771         minform = NULL;
 772     }
 773 }
 774
 775 double print (double value)
 776 {
 777     fprintf (stdout, format ? format : DEFAULT_FORMAT, value);
 778     fflush (stdout);
 779     return value;
 780 }
 781
 782 /* quit function */
 783
 784 void quit (void)
 785 {
 786     fprintf (stdout, "bye\n");
 787     exit (0);
 788 }
 789
 790 /* program function */
 791
 792 void prog (int id, element_t *root)
 793 {
 794     int i, n = -1;
 795
 796     if (programs == NULL) {
 797
 798         /* initial memory allocation */
 799         programs = (workspace_t *) callocordie (1, sizeof (workspace_t));
 800         nb_programs = 1;
 801         n = 0;
 802
 803     } else {
 804
 805         /* look for existing program */
 806         for (i = 0; i < nb_programs; i++) {
 807             if ((programs + i)->id == id) {
 808                 n = i;
 809                 break;
 810             }
 811         }
 812         if (n == -1) {
 813
 814             /* new program */
 815             n = nb_programs++;
 816             workspace_t *tmp = (workspace_t *) callocordie (nb_programs, sizeof (workspace_t));
 817             memcpy (tmp, programs, (nb_programs - 1) * sizeof (workspace_t));
 818             free (programs);
 819             programs = tmp;
 820         } else {
 821
 822             /* clean old program */
 823             if ((programs + n)->storage) {
 824                 free ((programs + n)->storage);
 825             }
 826             if ((programs + n)->stack) {
 827                 free ((programs + n)->stack);
 828             }
 829             if ((programs + n)->root) {
 830                 delelement ((programs + n)->root);
 831             }
 832             if ((programs + n)->string) {
 833                 free ((programs + n)->string);
 834                 (programs + n)->string = NULL;
 835             }
 836         }
 837     }
 838
 839     /* set program */
 840     (programs + n)->id = id;
 841     (programs + n)->answer = 0;
 842     (programs + n)->storage = NULL;
 843     (programs + n)->storage_size = 0;
 844     (programs + n)->stack = NULL;
 845     (programs + n)->stack_size = 0;
 846     (programs + n)->root = dupelement (root);
 847 }
 848
 849 double arg (int id)
 850 {
 851     double ret = 0;
 852     if ((id <= 0) || (id > argument_size)) {
 853         VERBOSE (WARNING, fprintf (stdout, "error out of bound (%d/%d)\n", id, argument_size));
 854     } else {
 855         ret = argument[id - 1];
 856     }
 857     return ret;
 858 }
 859
 860 double call (int id, int nbargs, element_t **args)
 861 {
 862     workspace_t tmp = {0};
 863     int i, l, n = -1;
 864     double ret = 0;
 865
 866     if (programs) {
 867
 868         /* look for program */
 869         for (i = 0; i < nb_programs; i++) {
 870             if ((programs + i)->id == id) {
 871                 n = i;
 872                 break;
 873             }
 874         }
 875     }
 876     if (n == -1) {
 877         VERBOSE (WARNING, fprintf (stdout, "error unknown program (%d)\n", id));
 878         return 0;
 879     }
 880
 881     /* store context */
 882     tmp.answer = answer;
 883     tmp.argument = argument;
 884     tmp.argument_size = argument_size;
 885     tmp.storage = storage;
 886     tmp.storage_size = storage_size;
 887     tmp.stack = stack;
 888     tmp.stack_size = stack_size;
 889
 890     /* change context */
 891     answer = 0;
 892     storage = (programs + n)->storage;
 893     storage_size = (programs + n)->storage_size;
 894     argument = NULL;
 895     argument_size = 0;
 896     stack = (programs + n)->stack;
 897     stack_size = (programs + n)->stack_size;
 898     if (nbargs > 0) {
 899         argument = (double *) callocordie (nbargs, sizeof (double));
 900         for (i = 0, l = 0; i < nbargs; l++) {
 901             if (args[l]) {
 902                 argument[i++] = evaluate_element (args[l], 0);
 903             }
 904         }
 905         argument_size = nbargs;
 906     }
 907
 908     /* evaluate program */
 909     element_t *elements = dupelement ((programs + n)->root);
 910     ret = evaluate_element (elements, 0);
 911     delelement (elements);
 912     (programs + n)->answer = answer;
 913     (programs + n)->storage = storage;
 914     (programs + n)->storage_size = storage_size;
 915     if (argument) {
 916         free (argument);
 917     }
 918     (programs + n)->stack = stack;
 919     (programs + n)->stack_size = stack_size;
 920
 921     /* restore context */
 922     answer = tmp.answer;
 923     storage = tmp.storage;
 924     storage_size = tmp.storage_size;
 925     argument = tmp.argument;
 926     argument_size = tmp.argument_size;
 927     stack = tmp.stack;
 928     stack_size = tmp.stack_size;
 929
 930     return ret;
 931 }
 932
 933 void list ()
 934 {
 935     int i;
 936     fprintf (stdout, "programs:");
 937     for (i = 0; i < nb_programs; i++) {
 938         fprintf (stdout, " %d", (programs + i)->id);
 939     }
 940     fprintf (stdout, "\n");
 941 }
 942
 943 void edit (int id)
 944 {
 945     int i, n = -1;
 946
 947     if (programs) {
 948
 949         /* look for program */
 950         for (i = 0; i < nb_programs; i++) {
 951             if ((programs + i)->id == id) {
 952                 n = i;
 953                 break;
 954             }
 955         }
 956     }
 957     if (n == -1) {
 958         VERBOSE (WARNING, fprintf (stdout, "error unknown program (%d)\n", id));
 959         return;
 960     }
 961
 962     /* set string program */
 963     fprintf (stdout, "edit: %s\n", (programs + n)->string);
 964 }
 965
 966 void savestring (int id, char *string)
 967 {
 968     int i, n = -1;
 969
 970     if (programs) {
 971
 972         /* look for program */
 973         for (i = 0; i < nb_programs; i++) {
 974             if ((programs + i)->id == id) {
 975                 n = i;
 976                 break;
 977             }
 978         }
 979     }
 980
 981     /* unnecesary code */
 982     //if (n == -1) {
 983     //    VERBOSE (WARNING, fprintf (stdout, "error unknown program (%d)\n", id));
 984     //    return;
 985     //}
 986     //if ((programs + n)->string) {
 987     //    free ((programs + n)->string);
 988     //}
 989
 990     if (string) {
 991         (programs + n)->string = strdup (string);
 992     }
 993 }
 994
 995 void del (int id)
 996 {
 997     int i, j, n = -1;
 998
 999     if (programs) {
1000
1001         /* look for program */
1002         for (i = 0; i < nb_programs; i++) {
1003             if ((programs + i)->id == id) {
1004                 n = i;
1005                 break;
1006             }
1007         }
1008     }
1009     if (n == -1) {
1010         VERBOSE (WARNING, fprintf (stdout, "error unknown program (%d)\n", id));
1011         return;
1012     }
1013
1014     /* clean program */
1015     if ((programs + n)->storage) {
1016         free ((programs + n)->storage);
1017     }
1018     if ((programs + n)->stack) {
1019         free ((programs + n)->stack);
1020     }
1021     if ((programs + n)->root) {
1022         delelement ((programs + n)->root);
1023     }
1024     if ((programs + n)->string) {
1025         free ((programs + n)->string);
1026     }
1027
1028     /* remove entry */
1029     workspace_t *tmp = (workspace_t *) callocordie (nb_programs - 1, sizeof (workspace_t));
1030     for (i = 0, j = 0; i < nb_programs; i++) {
1031         if (i != n) {
1032             memcpy (tmp + j, programs + i, sizeof (workspace_t));
1033             j++;
1034         }
1035     }
1036     free (programs);
1037     programs = tmp;
1038     nb_programs--;
1039 }
1040
1041 /* stack management */
1042
1043 double get (int n)
1044 {
1045     double ret = 0;
1046     if ((n <= 0) || (n > stack_size)) {
1047         VERBOSE (WARNING, fprintf (stdout, "error out of bound (%d/%d)\n", n, stack_size));
1048     } else {
1049         ret = stack[n - 1];
1050     }
1051     return ret;
1052 }
1053
1054 double length ()
1055 {
1056     return stack_size;
1057 }
1058
1059 double pop ()
1060 {
1061     double ret = 0;
1062     if (stack_size > 0) {
1063         ret = stack[--stack_size];
1064         double *tmp = (double *) callocordie (stack_size, sizeof (double));
1065         memcpy (tmp, stack, stack_size * sizeof (double));
1066         free (stack);
1067         stack = tmp;
1068     } else {
1069         VERBOSE (WARNING, fprintf (stdout, "error stack empty\n"));
1070     }
1071     return ret;
1072 }
1073
1074 double push (double val)
1075 {
1076     double *tmp = (double *) callocordie (stack_size + 1, sizeof (double));
1077     memcpy (tmp, stack, stack_size * sizeof (double));
1078     if (stack) {
1079         free (stack);
1080     }
1081     stack = tmp;
1082     stack[stack_size++] = val;
1083     return val;
1084 }
1085
1086 double put (int n, double val)
1087 {
1088     if (n <= 0) {
1089         VERBOSE (WARNING, fprintf (stdout, "error out of bound (%d/%d)\n", n, stack_size));
1090         return 0;
1091     }
1092     if (n > stack_size) {
1093         double *tmp = (double *) callocordie (n, sizeof (double));
1094         memcpy (tmp, stack, stack_size * sizeof (double));
1095         free (stack);
1096         stack = tmp;
1097         stack_size = n;
1098     }
1099     stack[n - 1] = val;
1100     return val;
1101 }
1102
1103 double set (int nbops, element_t **ops)
1104 {
1105     int i;
1106     if (stack) {
1107         free (stack);
1108     }
1109     stack = NULL;
1110     stack_size = 0;
1111     if (nbops != 0) {
1112          stack = (double *) callocordie (nbops, sizeof (double));
1113          for (i = 0; i < nbops; i++) {
1114              stack[i] = evaluate_element (ops[i], 0);
1115          }
1116          stack_size = nbops;
1117     }
1118     return stack_size;
1119 }
1120
1121 void show (void)
1122 {
1123     int i;
1124     fprintf (stdout, "stack:");
1125     for (i = 0; i < stack_size; i++) {
1126         fprintf (stdout, " ");
1127         fprintf (stdout, minform, stack[i]);
1128     }
1129     fprintf (stdout, "\n");
1130 }
1131
1132 /* stack functions */
1133
1134 double max ()
1135 {
1136     double ret = 0;
1137     int i;
1138     if (stack_size < 1) {
1139         VERBOSE (WARNING, fprintf (stdout, "error not enough element in stack (%d)\n", stack_size));
1140         return 0;
1141     }
1142     ret = stack[0];
1143     for (i = 1; i < stack_size; i++) {
1144         if (stack[i] > ret) {
1145             ret = stack[i];
1146         }
1147     }
1148     return ret;
1149 }
1150
1151 double mean ()
1152 {
1153     double ret = 0;
1154     int i;
1155     if (stack_size < 1) {
1156         VERBOSE (WARNING, fprintf (stdout, "error not enough element in stack (%d)\n", stack_size));
1157         return 0;
1158     }
1159     for (i = 0; i < stack_size; i++) {
1160         ret += stack[i];
1161     }
1162     return ret / stack_size;
1163 }
1164
1165 double min ()
1166 {
1167     double ret = 0;
1168     int i;
1169     if (stack_size < 1) {
1170         VERBOSE (WARNING, fprintf (stdout, "error not enough element in stack (%d)\n", stack_size));
1171         return 0;
1172     }
1173     ret = stack[0];
1174     for (i = 1; i < stack_size; i++) {
1175         if (stack[i] < ret) {
1176             ret = stack[i];
1177         }
1178     }
1179     return ret;
1180 }
1181
1182 void order ()
1183 {
1184     int i, j;
1185     if (stack_size < 1) {
1186         VERBOSE (WARNING, fprintf (stdout, "error not enough element in stack (%d)\n", stack_size));
1187         return;
1188     }
1189     for (i = 0; i < stack_size - 1; i++) {
1190         int done = 0;
1191         for (j = 0; j < stack_size - 1; j++) {
1192             if (stack[j] > stack[j + 1]) {
1193                 double tmp = stack[j];
1194                 stack[j] = stack[j + 1];
1195                 stack[j + 1] = tmp;
1196                 done = 1;
1197             }
1198         }
1199         if (done == 0) {
1200             break;
1201         }
1202     }
1203 }
1204
1205 double median ()
1206 {
1207     double ret = 0;
1208     if (stack_size < 3) {
1209         VERBOSE (WARNING, fprintf (stdout, "error not enough element in stack (%d)\n", stack_size));
1210         return 0;
1211     }
1212     double *tmp = (double *) callocordie (stack_size, sizeof (double));
1213     memcpy (tmp, stack, stack_size * sizeof (double));
1214     order ();
1215     ret = stack[(stack_size - 1)/ 2];
1216     memcpy (stack, tmp, stack_size * sizeof (double));
1217     free (tmp);
1218     return ret;
1219 }
1220
1221 double prod ()
1222 {
1223     double ret = 1;
1224     int i;
1225     if (stack_size < 1) {
1226         VERBOSE (WARNING, fprintf (stdout, "error not enough element in stack (%d)\n", stack_size));
1227         return 0;
1228     }
1229     for (i = 0; i < stack_size; i++) {
1230         ret *= stack[i];
1231     }
1232     return ret;
1233 }
1234
1235 double sum ()
1236 {
1237     double ret = 0;
1238     int i;
1239     if (stack_size < 1) {
1240         VERBOSE (WARNING, fprintf (stdout, "error not enough element in stack (%d)\n", stack_size));
1241         return 0;
1242     }
1243     for (i = 0; i < stack_size; i++) {
1244         ret += stack[i];
1245     }
1246     return ret;
1247 }
1248
1249 double variance ()
1250 {
1251     double ret = 0;
1252     double m = 0;
1253     int i;
1254     if (stack_size < 2) {
1255         VERBOSE (WARNING, fprintf (stdout, "error not enough element in stack (%d)\n", stack_size));
1256         return 0;
1257     }
1258     m = mean ();
1259     for (i = 0; i < stack_size; i++) {
1260         ret += (stack[i] - m) * (stack[i] - m);
1261     }
1262     return ret / stack_size;
1263 }
1264
1265
1266 /* help message */
1267
1268 void help (void)
1269 {
1270     fprintf (stdout, "calc is a simple calculator\n\n");
1271     fprintf (stdout, "arithmetic op.:");
1272     fprintf (stdout, " + - * / %% ^\n");
1273     fprintf (stdout, "comparison op.:");
1274     fprintf (stdout, " == != >= <= > <\n");
1275     fprintf (stdout, "logical op.:");
1276     fprintf (stdout, " & | !\n");
1277     fprintf (stdout, "mathematic func.:");
1278     fprintf (stdout, " exp ln log pow sqrt\n");
1279     fprintf (stdout, "trigonometric func.:");
1280     fprintf (stdout, " acos asin atan cos sin tan\n");
1281     fprintf (stdout, "error functions:");
1282     fprintf (stdout, " erf erfc\n");
1283     fprintf (stdout, "miscellaneous func.:");
1284     fprintf (stdout, " abs ceil floor\n");
1285     fprintf (stdout, "storage func.:");
1286     fprintf (stdout, " clear dec disp inc mem rcl sto\n");
1287     fprintf (stdout, "control flow prim.:");
1288     fprintf (stdout, " cond print while {} ;\n");
1289     fprintf (stdout, "program management:");
1290     fprintf (stdout, " arg call del edit ls prog\n");
1291     fprintf (stdout, "stack management:");
1292     fprintf (stdout, " get len pop push put set show\n");
1293     fprintf (stdout, "stack func.:");
1294     fprintf (stdout, " max mean med min ord prod sum var\n");
1295     fprintf (stdout, "control management:");
1296     fprintf (stdout, " help quit\n");
1297     fprintf (stdout, "constants:");
1298     fprintf (stdout, " ans e pi\n");
1299 }
1300
1301 /* evaluate element tree */
1302
1303 #define MASK_SUB 0x1
1304 #define MASK_DIV 0x2
1305
1306 double evaluate_element (element_t *root, char mask)
1307 {
1308     double op0 = 0, op1 = 0;
1309     char nextmask = mask;
1310     int i, nb;
1311
1312     if ((root == NULL) || (root == ERROR_OP)) {
1313         VERBOSE (WARNING, fprintf (stdout, "error while evaluating\n"));
1314         return 0;
1315     }
1316
1317     /* mask to manage sub operator sub and div */
1318     switch (root->func) {
1319     case Add:
1320         nextmask &= ~MASK_SUB;
1321         nextmask &= ~MASK_DIV;
1322         break;
1323     case Sub:
1324         nextmask |= MASK_SUB;
1325         nextmask &= ~MASK_DIV;
1326         break;
1327     case Mul:
1328         nextmask &= ~MASK_DIV;
1329         break;
1330     case Div:
1331         nextmask |= MASK_DIV;
1332         break;
1333     default:
1334         nextmask = mask;
1335     }
1336
1337     switch (root->func) {
1338     case Val:
1339     case Sig:
1340         op0 = (root->ops[0]) ? evaluate_element (root->ops[0], nextmask) : root->value;
1341         break;
1342     case Add:
1343     case Sub:
1344     case Mul:
1345     case Div:
1346     case Mod:
1347     case Pow:
1348     case Store:
1349     case Equal:
1350     case Diff:
1351     case Ge:
1352     case Le:
1353     case Gt:
1354     case Lt:
1355     case And:
1356     case Or:
1357         if (root->ops[1]) {
1358             op1 = evaluate_element (root->ops[1], nextmask);
1359         } else if (root->func != Store) {
1360             VERBOSE (WARNING, fprintf (stdout, "error while evaluating (op[1])\n"));
1361             return 0;
1362         }
1363         /* fallthrough */
1364     case Sqr:
1365     case Cos:
1366     case Sin:
1367     case Tan:
1368     case Acos:
1369     case Asin:
1370     case Atan:
1371     case Ln:
1372     case Log:
1373     case Exp:
1374     case Erfc:
1375     case Erf:
1376     case Abs:
1377     case Ceil:
1378     case Floor:
1379     case Recall:
1380     case Inc:
1381     case Dec:
1382     case Not:
1383     case Mem:
1384     case Cond:
1385     case Prog:
1386     case Arg:
1387     case Call:
1388     case Edit:
1389     case Del:
1390     case Get:
1391         if (root->ops[0]) {
1392             op0 = evaluate_element (root->ops[0], 0);
1393         } else {
1394             VERBOSE (WARNING, fprintf (stdout, "error while evaluating (op[0])\n"));
1395             return 0;
1396         }
1397         break;
1398     case Disp:
1399     case Clear:
1400     case Quit:
1401     case Help:
1402     case Ans:
1403     case Pi:
1404     case E:
1405     case Code:
1406     case List:
1407     case Length:
1408     case Pop:
1409     case Set:
1410     case Show:
1411     case Median:
1412     case Order:
1413     case Prod:
1414     case Sum:
1415         break;
1416     case While:
1417         if (root->ops[0] == NULL) {
1418             VERBOSE (WARNING, fprintf (stdout, "error while evaluating (op[0])\n"));
1419             return 0;
1420         }
1421         break;
1422     case Push:
1423     case Print:
1424         op0 = (root->ops[0]) ? evaluate_element (root->ops[0], 0) : answer;
1425         break;
1426     case Put:
1427         if (root->ops[0]) {
1428             op0 = evaluate_element (root->ops[0], 0);
1429         } else {
1430             VERBOSE (WARNING, fprintf (stdout, "error while evaluating (op[0])\n"));
1431             return 0;
1432         }
1433         op1 = (root->ops[1]) ? evaluate_element (root->ops[1], 0) : answer;
1434         break;
1435     case Max:
1436     case Mean:
1437     case Min:
1438     case Variance:
1439         if (root->ops[0]) {
1440             op0 = evaluate_element (root->ops[0], 0);
1441             op1 = (root->ops[1]) ? evaluate_element (root->ops[1], 0) : answer;
1442         }
1443     }
1444
1445     switch (root->func) {
1446     case Val: return op0;
1447     case Sig: return -op0;
1448     case Add: return ((mask & MASK_SUB) == 0) ? op0 + op1 : op0 - op1;
1449     case Sub: return ((mask & MASK_SUB) == 0) ? op0 - op1 : op0 + op1;
1450     case Mul: return ((mask & MASK_DIV) == 0) ? op0 * op1 : op0 / op1;
1451     case Div: return ((mask & MASK_DIV) == 0) ? op0 / op1 : op0 * op1;
1452     case Mod: return fmod (op0, op1);
1453     case Pow: return pow (op0, op1);
1454     case Sqr: return sqrt (op0);
1455     case Cos: return cos (op0);
1456     case Sin: return sin (op0);
1457     case Tan: return tan (op0);
1458     case Acos: return acos (op0);
1459     case Asin: return asin (op0);
1460     case Atan: return atan (op0);
1461     case Ln: return log (op0);
1462     case Log: return log10 (op0);
1463     case Exp: return exp (op0);
1464     case Erfc: return erfc (op0);
1465     case Erf: return erf (op0);
1466     case Abs: return fabs (op0);
1467     case Ceil: return ceil (op0);
1468     case Floor: return floor (op0);
1469     case Store: return store ((int)op0, (op1) ? op1 : answer);
1470     case Recall: return recall ((int)op0);
1471     case Inc: return increase ((int)op0);
1472     case Dec: return decrease ((int)op0);
1473     case Disp: display (); break;
1474     case Mem: memory ((int)op0); break;
1475     case Clear: clear (); break;
1476     case Quit: quit (); break;
1477     case Help: help (); break;
1478     case Ans: return answer;
1479     case Pi: return M_PI;
1480     case E: return M_E;
1481     case Equal: return op0 == op1;
1482     case Diff: return op0 != op1;
1483     case Ge: return op0 >= op1;
1484     case Le: return op0 <= op1;
1485     case Gt: return op0 > op1;
1486     case Lt: return op0 < op1;
1487     case And: return (op0 != 0) && (op1 != 0);
1488     case Or: return (op0 != 0) || (op1 != 0);
1489     case Not: return (op0 == 0);
1490     case Cond:
1491         if ((op0) && (root->ops[1])) {
1492             return evaluate_element (root->ops[1], 0);
1493         } else if ((!op0) && (root->ops[2])) {
1494             return evaluate_element (root->ops[2], 0);
1495         } else {
1496             return 0;
1497         }
1498     case While: return while_do (root->ops[0], root->ops[1]);
1499     case Code: return execute_code (root->ops, root->nbops);
1500     case Print: return print (op0);
1501     case Prog:
1502         prog ((int)op0, root->ops[1]);
1503         savestring ((int)op0, root->string);
1504         break;
1505     case Arg: return arg ((int)op0);
1506     case Call:
1507         for (i = 1, nb =0; i < root->nbops; i++) {
1508             if (root->ops[i]) {
1509                 nb++;
1510             }
1511         }
1512         return call ((int)op0, nb, root->ops + 1);
1513     case List: list (); break;
1514     case Edit: edit ((int)op0); break;
1515     case Del: del ((int)op0); break;
1516     case Get: return get ((int)op0);
1517     case Length: return length ();
1518     case Pop: return pop ();
1519     case Push: return push (op0);
1520     case Put: return put ((int)op0, op1);
1521     case Set:
1522         for (i = 0, nb =0; i < root->nbops; i++) {
1523             if (root->ops[i]) {
1524                 nb++;
1525             }
1526         }
1527         return set (nb, root->ops);
1528     case Show: show (); break;
1529     case Max:
1530         if (root->ops[0]) {
1531             return op0 > op1 ? op0 : op1;
1532         }
1533         return max ();
1534     case Mean:
1535         if (root->ops[0]) {
1536             return (op0 + op1) / 2;
1537         }
1538         return mean ();
1539     case Median: return median ();
1540     case Min:
1541         if (root->ops[0]) {
1542             return op0 < op1 ? op0 : op1;
1543         }
1544         return min ();
1545     case Order: order (); break;
1546     case Prod: return prod ();
1547     case Sum: return sum ();
1548     case Variance:
1549         if (root->ops[0]) {
1550             double m = (op0 + op1) / 2;
1551             op0 -= m;
1552             op1 -= m;
1553             return op0 * op0 + op1 * op1;
1554         }
1555         return variance ();
1556     }
1557
1558     return 0;
1559 }
1560
1561 char **generate_completion_list ()
1562 {
1563     int i, j, l = 0;
1564     char **list = (char **) callocordie (NB_OPERATORS + NB_FUNCTIONS + NB_CONSTANTS + NB_SYMBOLS + 1, sizeof (char *));
1565
1566     for (i = 0; i < NB_OPERATORS; i++) {
1567         list[l] = strdup ((operators + i)->keyword);
1568         for (j = 0; j < (int)strlen (list[l]); j++) {
1569             if (list[i][j] == '\t') {
1570                 list[i][j] = '\0';
1571             }
1572         }
1573         if (list[l] != NULL) {
1574             l++;
1575         }
1576     }
1577
1578     for (i = 0; i < NB_FUNCTIONS; i++) {
1579         list[l] = strdup ((functions + i)->keyword);
1580         if (list[l] != NULL) {
1581             l++;
1582         }
1583     }
1584
1585     for (i = 0; i < NB_CONSTANTS; i++) {
1586         list[l] = strdup ((constants + i)->keyword);
1587         if (list[l] != NULL) {
1588             l++;
1589         }
1590     }
1591
1592     for (i = 0; i < NB_SYMBOLS; i++) {
1593         list[l] = strdup (symbols[i]);
1594         if (list[l] != NULL) {
1595             l++;
1596         }
1597     }
1598
1599     return (list);
1600 }
1601
1602 void free_completion_list (char **list)
1603 {
1604     int i;
1605
1606     if (list) {
1607         for (i = 0; i < NB_OPERATORS + NB_FUNCTIONS + NB_CONSTANTS + NB_SYMBOLS + 1; i++) {
1608             if (list[i] != NULL) {
1609                 free (list[i]);
1610             }
1611         }
1612         free (list);
1613     }
1614 }
1615
1616
1617 /* vim: set ts=4 sw=4 et: */