fooobject.h

用于词法分析的词法分析器

/*
  $Id: FooObject.h,v 1.7 1997/02/02 01:31:01 matt Exp $

  FooObject class.
  
  (c) July 96 Matt Phillips
*/

#ifndef _FOO_OBJECT_H
#define _FOO_OBJECT_H

#include <std/string.h>
#include <util/strhash.h>
#include <contain/LinkedListWithTail.h>
#include <contain/OpenHash.h>

class FooObject
{
public:

  class Hash
  {
  public:
    static int hash (const string &str) {return ::hash (str);}
  };

  typedef TypeIOLinkedListWithTail(FooObject) Objects;
  typedef TypeIOOpenHash(string, Objects, Hash) Attrs;
  typedef Attrs::Iterator Iterator;

  FooObject ();
  FooObject (const string &value);
  ~FooObject ();

  // 				 add
  //----------------------------------------------------------------------

  // add value to list for attr.
  void addAttr (const string &attr, FooObject &value);
  // add values to list for attr.
  void addAttr (const string &attr, const Objects &values);
  // add (or replace) string value attribute.
  void addAttr (const string &value);

  // 				remove
  //----------------------------------------------------------------------

  // returns true if attr was sucessfully deleted.
  int removeAttr (const string &attr);
  // returns true if string value attribute was sucessfully deleted.
  int removeAttr ();

  // 				 get
  //----------------------------------------------------------------------

  // return values for attr, an empty list is returned if attr does
  // not exist.
  const Objects &getAttrs (const string &attr) const;

  // return values for attr. attr is created if it does not exist.
  Objects &getOrCreateAttrs (const string &attr);

  // returns last value of attr or null if attribute does not exist.
  FooObject *getAttr (const string &attr) const;

  // returns string value attribute or empty string if attr does not
  // exist.
  const string &getAttr () const;
  int getAttrInt () const;

  // returns string value attribute or creates it if attr does not
  // exist.
  string &getOrCreateAttr ();

  // return string value attribute of object referenced by attr or ''
  // if attr does not exist.
  const string &getAttrString (const string &attr) const;

  // return int conversion of string value attribute of object
  // referenced by attr or 0 if attr does not exist or is not a
  // number.
  int getAttrInt (const string &attr) const;

  // return an iterator for all attributes in object except string
  // value attribute.
  Iterator getIter () const;

  // 			get via attribute path
  //----------------------------------------------------------------------

  // returns last value of values pointed to by attribute path.
  FooObject *getAttrPath (const string &path) const;
  // returns values for attribute path of form 'attr1/attr2/...' or
  // null if any element of path does not exist.
  Objects *getAttrsPathPtr (const string &attr) const;
  // returns values for attribute path or empty list if any element of
  // path does not exist.
  const Objects &getAttrsPath (const string &attr) const;
  // returns string attribute of object at end of path or null if any
  // element of path does not exist.
  string *getAttrStringPathPtr (const string &path) const;
  // returns string attribute of object at end of path or '' if any
  // element of path does not exist.
  const string &getAttrStringPath (const string &path) const;
  // same as getAttrInt () but follows an attribute path.  returns 0
  // if path does not exist or where getAttrInt () would return 0.
  int getAttrIntPath (const string &path) const;

  // 				 misc
  //----------------------------------------------------------------------

  // true if object has an attribute called attr.
  int hasAttr (const string &attr) const {return attrs && attrs->get (attr);}

  // true if object has a string value attribute.
  int hasAttr () const {return stringValue != 0;}

  // returns the number of attributes in this object except the string
  // value.
  int nAttrs () const;

  // true if object has no attributes except the string value.
  int isAtomic () const {return hasAttr () && nAttrs () == 0;}

protected:

  Objects *getAttrValues (const string &attr) const;

  Attrs *attrs;
  string *stringValue;
  static const Objects emptyList;
  static const Attrs emptyAttrs;
  static const string emptyString;
};

#endif