text: /*****************************************************************************/
  /*                                                                           */
  /*                                studyexpr.h                                */
  /*                                                                           */
  /*                         Study an expression tree                          */
  /*                                                                           */
  /*                                                                           */
  /*                                                                           */
  /* (C) 2003-2012,  Ullrich von Bassewitz                                     */
  /*                 Roemerstrasse 52                                          */
  /*                 D-70794 Filderstadt                                       */
  /* EMail:          uz@cc65.org                                               */
  /*                                                                           */
  /*                                                                           */
  /* This software is provided 'as-is', without any expressed or implied       */
  /* warranty.  In no event will the authors be held liable for any damages    */
  /* arising from the use of this software.                                    */
  /*                                                                           */
  /* Permission is granted to anyone to use this software for any purpose,     */
  /* including commercial applications, and to alter it and redistribute it    */
  /* freely, subject to the following restrictions:                            */
  /*                                                                           */
  /* 1. The origin of this software must not be misrepresented; you must not   */
  /*    claim that you wrote the original software. If you use this software   */
  /*    in a product, an acknowledgment in the product documentation would be  */
  /*    appreciated but is not required.                                       */
  /* 2. Altered source versions must be plainly marked as such, and must not   */
  /*    be misrepresented as being the original software.                      */
  /* 3. This notice may not be removed or altered from any source              */
  /*    distribution.                                                          */
  /*                                                                           */
  /*****************************************************************************/
  
  
  
  #ifndef STUDYEXPR_H
  #define STUDYEXPR_H
  
  
  
  /* common */
  #include "exprdefs.h"
  
  
  
  /*****************************************************************************/
  /*                                   Data                                    */
  /*****************************************************************************/
  
  
  
  /* Flags */
  #define ED_OK           0x00            /* Nothing special */
  #define ED_TOO_COMPLEX  0x01            /* Expression is too complex */
  #define ED_ERROR        0x02            /* Error evaluating the expression */
  
  /* Symbol reference */
  typedef struct ED_SymRef ED_SymRef;
  struct ED_SymRef {
      long                Count;          /* Number of references */
      struct SymEntry*    Ref;            /* Actual reference */
  };
  
  /* Section reference */
  typedef struct ED_SecRef ED_SecRef;
  struct ED_SecRef {
      long                Count;          /* Number of references */
      unsigned            Ref;            /* Actual reference */
  };
  
  /* Structure for parsing expression trees */
  typedef struct ExprDesc ExprDesc;
  struct ExprDesc {
      unsigned short      Flags;          /* See ED_xxx */
      unsigned char       AddrSize;       /* Address size of the expression */
      long                Val;            /* The offset value */
      long                Right;          /* Right value for StudyBinaryExpr */
  
      /* Symbol reference management */
      unsigned            SymCount;       /* Number of symbols referenced */
      unsigned            SymLimit;       /* Memory allocated */
      ED_SymRef*          SymRef;         /* Symbol references */
  
      /* Section reference management */
      unsigned            SecCount;       /* Number of sections referenced */
      unsigned            SecLimit;       /* Memory allocated */
      ED_SecRef*          SecRef;         /* Section references */
  };
  
  
  
  /*****************************************************************************/
  /*                              struct ExprDesc                              */
  /*****************************************************************************/
  
  
  
  ExprDesc* ED_Init (ExprDesc* ED);
  /* Initialize an ExprDesc structure for use with StudyExpr */
  
  void ED_Done (ExprDesc* ED);
  /* Delete allocated memory for an ExprDesc. */
  
  int ED_IsConst (const ExprDesc* ED);
  /* Return true if the expression is constant */
  
  
  
  /*****************************************************************************/
  /*                                   Code                                    */
  /*****************************************************************************/
  
  
  
  void StudyExpr (ExprNode* Expr, ExprDesc* D);
  /* Study an expression tree and place the contents into D */
  
  
  
  /* End of studyexpr.h */
  
  #endif
  