eval_trans_tree.c

来自「Gambas is a graphical development enviro」· C语言 代码 · 共 135 行

/***************************************************************************

  trans_tree.c

  Convert expression to a tree

  (c) 2000-2003 Beno顃 Minisini <[e-mail]>

  This program is free software; you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation; either version 1, or (at your option)
  any later version.

  This program is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with this program; if not, write to the Free Software
  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

***************************************************************************/

#define __TRANS_TREE_C

#include "gb_common.h"
#include "gb_error.h"
#include "gb_reserved.h"

#include "eval_trans.h"
#include "eval_read.h"
#include "eval.h"

/*#define DEBUG*/

PRIVATE short level;
PRIVATE PATTERN *current;
/*PRIVATE PATTERN last_pattern;*/

PRIVATE void analyze_expr(short priority, short op_main);


PRIVATE void inc_level()
{
  level++;
  if (level > MAX_EXPR_LEVEL)
   THROW("Expression too complex");
}


PRIVATE void dec_level()
{
  level--;
}


PRIVATE void add_pattern(PATTERN pattern)
{
  PATTERN *node;
  short index;

  index = (short)ARRAY_count(EVAL->tree);

  if (index >= MAX_EXPR_PATTERN)
    THROW("Expression too complex");

  node = ARRAY_add(&EVAL->tree);
  *node = pattern;
  /*last_pattern = pattern;*/


  /*#ifdef DEBUG
  READ_dump_pattern(&pattern);
  #endif*/
}


PRIVATE void remove_last_pattern()
{
  if (!ARRAY_count(EVAL->tree))
    return;

  ARRAY_remove_last(&EVAL->tree);
}


PRIVATE PATTERN get_last_pattern(int dep)
{
  short index;

  index = (short)ARRAY_count(EVAL->tree);
  if (index < dep)
    return NULL_PATTERN;

  return EVAL->tree[index - dep];
}


PRIVATE void change_last_pattern(int dep, PATTERN pattern)
{
  short index;

  index = (short)ARRAY_count(EVAL->tree);
  if (index < dep)
    return;

  EVAL->tree[index - dep] = pattern;
}


PRIVATE void check_last_first(int dep)
{
  if (PATTERN_is_identifier(get_last_pattern(dep)))
    change_last_pattern(dep, PATTERN_set_flag(get_last_pattern(dep), RT_FIRST));
}


PRIVATE void add_reserved_pattern(int reserved)
{
  add_pattern(PATTERN_make(RT_RESERVED, reserved));
}



PRIVATE void add_operator_output(short op, short nparam, boolean has_output)
{
  PATTERN pattern;
  long index;
  SYMBOL *sym;

  /*
     A QUOI SERT CE TEST ?

     add_operator() peut 阾re appel