Copy the KDE 3.5 branch to branches/trinity for new KDE 3.5 features.

BUG:215923


git-svn-id: svn://anonsvn.kde.org/home/kde/branches/trinity/kdewebdev@1054174 283d02a7-25f6-0310-bc7c-ecb5cbfe19da

1 files changed, 80 insertions, 0 deletions

diff --git a/kommander/widget/expression.h b/kommander/widget/expression.h
new file mode 100644
index 00000000..7ab163e2
--- /dev/null
+++ b/kommander/widget/expression.h
@@ -0,0 +1,80 @@
+/***************************************************************************
+                    expression.h - Expression parser
+                             -------------------
+    copyright          : (C) 2004      Michal Rudolf <mrudolf@kdewebdwev.org>
+
+ ***************************************************************************/
+
+/***************************************************************************
+ *                                                                         *
+ *   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 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ *                                                                         *
+ ***************************************************************************/
+
+#ifndef _HAVE_EXPRESSION_H_
+#define _HAVE_EXPRESSION_H_
+
+#include <qstring.h>
+#include <qvaluelist.h>
+#include <qvariant.h>
+
+class Expression
+{
+public:
+  Expression();
+  Expression(const QString& expr);
+  /* set string to parse */
+  Expression& operator=(const QString& s);
+  /* calculate value */
+  QVariant value(bool* valid = 0);
+  /* equivalent of setString(s) and value(valid) */
+  QVariant value(const QString& s, bool* valid = 0);
+  /* equivalent of setString(s) and checking if value(valid) is true */
+  bool isTrue(const QString& s, bool* valid = 0);
+private:
+  enum Type {TypeInt, TypeDouble, TypeString};
+  /* parsing function - top-down approach */
+  /* parse terminal (number or string) */
+  QVariant parseNumber();
+  /* parse -x expression */
+  QVariant parseMinus();
+  /* parse (x) expression */
+  QVariant parseBracket();
+  /* parse x*y, x/y and x%y expressions */
+  QVariant parseMultiply();
+  /* parse x+y and x-y expressions */
+  QVariant parseAdd();
+  /* parse !x and (equivalent) not x expressions */
+  QVariant parseNot();
+  /* parse x==y, x<=y, x>=y, x<y and x>y expressions */
+  QVariant parseComparison();
+  /* parse x && y, (equivalent) x and y expressions */
+  QVariant parseAnd();
+  /* parse x || y and  (equivalent) x or y expressions */
+  QVariant parseOr();
+  /* starting point of parsing - just call first function above */
+  QVariant parse();
+
+  /* check if we still have next argument */
+  bool validate();
+  /* return next argument to parse or null if there is none */
+  QString next() const;
+  /* set error position for future error reporting */
+  void setError(int pos = -1);
+  /* compare various types of QVariant (strings, floats, ints */
+  int compare(const QVariant v1, const QVariant v2) const; 
+  /* return common type for binary operations */
+  Type commonType(const QVariant v1, const QVariant v2) const; 
+
+  QValueList<QVariant> m_parts;
+  uint m_start;
+  bool m_error;
+  uint m_errorPosition;
+
+};
+
+#endif
+