Harbour implementation of Class(y) Class Symbol

harbour/source/rtl/symbol.prg

@@ -0,0 +1,168 @@
+/*
+ * $Id$
+ */
+
+/*
+ * Harbour Project source code:
+ * Harbour implementation of Class(y) Class Symbol
+ *
+ * Copyright 2003 Antonio Linares <alinares@fivetechsoft.com>
+ * www - http://www.harbour-project.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, 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 software; see the file COPYING.  If not, write to
+ * the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
+ * Boston, MA 02111-1307 USA (or visit the web site http://www.gnu.org/).
+ *
+ * As a special exception, the Harbour Project gives permission for
+ * additional uses of the text contained in its release of Harbour.
+ *
+ * The exception is that, if you link the Harbour libraries with other
+ * files to produce an executable, this does not by itself cause the
+ * resulting executable to be covered by the GNU General Public License.
+ * Your use of that executable is in no way restricted on account of
+ * linking the Harbour library code into it.
+ *
+ * This exception does not however invalidate any other reasons why
+ * the executable file might be covered by the GNU General Public License.
+ *
+ * This exception applies only to the code released by the Harbour
+ * Project under the name Harbour.  If you copy code from other
+ * Harbour Project or Free Software Foundation releases into a copy of
+ * Harbour, as the General Public License permits, the exception does
+ * not apply to the code that you add in this way.  To avoid misleading
+ * anyone as to the status of such modified files, you must delete
+ * this exception notice from them.
+ *
+ * If you write modifications of your own for Harbour, it is your choice
+ * whether to permit this exception to apply to your modifications.
+ * If you do not wish that, delete this exception notice.
+ *
+ */
+
+/* uncomment this section for a working sample
+
+// Class(y) Class Symbol documentation is located at:
+// http://www.clipx.net/ng/classy/ngdebc.php
+
+function Main()
+
+   local oSym := Symbol():New( "QOUT" )
+
+   ? "Now test the :Exec() method"
+
+   oSym:Exec( "This string is being printed by QOUT" )
+   oSym:Exec( "which is being invoked by the :Exec()" )
+   oSym:Exec( "method in the Symbol class." )
+
+   ?
+   ? "symbol name: ", oSym:name
+
+   ? "Comparing QOut symbol with xOut symbol"
+   ? oSym:IsEqual( Symbol():New( "xOut" ) )
+
+   ? "done!"
+   ?
+
+return nil */
+
+#include "hbclass.ch"
+
+CLASS Symbol
+
+   DATA   nSym  HIDDEN       // internal pointer to the Symbols table symbol
+
+   METHOD New( cSymName )    // Constructor. cSymName may already exists or not
+
+   METHOD IsEqual( oSymbol ) // Compares two symbol objects
+
+   METHOD exec() // Executes the function referred to by the Symbol object,
+                 // with an optional parameters list
+
+   METHOD _name( cName ) VIRTUAL // name simulates a read-only DATA so it
+                                 // can't be assigned
+   METHOD name() INLINE GetSymbolName( ::nSym ) // retrieves the symbol name
+
+ENDCLASS
+
+METHOD New( cSymName ) CLASS Symbol
+
+   ::nSym = GetSymbolPointer( cSymName )
+
+return Self
+
+METHOD IsEqual( oSymbol ) CLASS Symbol
+
+   if ValType( oSymbol ) == "O"
+      return ::nSym == oSymbol:nSym
+   endif
+
+return .f.
+
+#pragma BEGINDUMP
+
+#include <hbapi.h>
+#include <hbvm.h>
+
+static HB_FUNC( GETSYMBOLPOINTER )
+{
+   hb_retnl( ( long ) hb_dynsymGet( hb_parc( 1 ) ) );
+}
+
+static HB_FUNC( GETSYMBOLNAME )
+{
+   PHB_DYNS pDynSym = ( PHB_DYNS ) hb_parnl( 1 );
+
+   hb_retc( ( pDynSym != NULL ? pDynSym->pSymbol->szName : "" ) );
+}
+
+static HB_FUNC( SYMBOL_EXEC )
+{
+   PHB_ITEM pSelf = hb_param( 0, HB_IT_OBJECT ); /* we retrieve Self */
+   PHB_DYNS pSym;
+
+   static PHB_DYNS pDynSym = NULL; /* We use a static value to look for the
+                                      symbol nSym just once */
+   if( pDynSym == NULL )
+      pDynSym = hb_dynsymFindName( "nSym" );
+
+   /* Lets retrieve DATA nSym from Self,
+      first we place the nSym symbol at the HVM stack */
+   hb_vmPushSymbol( pDynSym->pSymbol );
+
+   /* we place the object at the HVM stack */
+   hb_vmPush( pSelf );
+
+   /* we invoke the message with no parameters */
+   hb_vmFunction( 0 );
+
+   pSym = ( PHB_DYNS ) hb_parnl( -1 );  /* we take the returned DATA value from
+                                           the HVM hb_stack.Return */
+   if( pSym != NULL && pSym->pSymbol->pFunPtr )
+   {
+      int i;
+
+      hb_vmPushSymbol( pSym->pSymbol );
+      hb_vmPushNil(); /* No Self. We are going to execute a function or a procedure */
+
+      for( i = 1; i <= hb_pcount(); i++ ) /* number of supplied params */
+         /* pushes a generic item (supplied parameter) to the HVM */
+         hb_vmPush( hb_param( i, HB_IT_ANY ) );
+
+      hb_vmFunction( hb_pcount() ); /* executes the symbol */
+   }
+   else
+      hb_ret();  /* clean the HVM hb_stack.Return */
+}
+
+#pragma ENDDUMP