Working on the parser, some issues.

1 files changed, 38 insertions, 4 deletions

diff --git a/src/lexer.cpp b/src/lexer.cpp
index b0d0fd1..fbcaafb 100644
--- a/src/lexer.cpp
+++ b/src/lexer.cpp
@@ -11,27 +11,55 @@ Lexer::Lexer( Bu::Stream &rIn ) :
     iRadix( 10 ),

     numRangeTop('9'),

     ascRangeTop('a'-1),

-    eMode( modeNormal )

+    eMode( modeNormal ),

+    iLookAheadSize( 2 ),

+    iLookAheadUsed( 0 ),

+    iLookAheadStart( 0 ),

+    aLookAhead( 0 )

 {

+    aLookAhead = new Token[iLookAheadSize];

 }

 

 Lexer::~Lexer()

 {

 }

 

-Token Lexer::nextToken()

+void Lexer::nextToken()

+{

+    if( iLookAheadSize <= 1 )

+    {

+        iLookAheadSize = 0;

+        iLookAheadStart = 0;

+    }

+    else

+    {

+        iLookAheadStart = (iLookAheadStart+1)%iLookAheadSize;

+        iLookAheadSize--;

+    }

+}

+

+void Lexer::fillToken()

 {

     switch( eMode )

     {

         case modeNormal:

-            return nextTokenNormal();

+            aLookAhead[(iLookAheadUsed+iLookAheadStart)%iLookAheadSize] =

+                nextTokenNormal();

+            break;

 

         case modeCommand:

-            return nextTokenCommand();

+            aLookAhead[(iLookAheadUsed+iLookAheadStart)%iLookAheadSize] =

+                nextTokenCommand();

+            break;

 

         default:

             throw Bu::ExceptionBase("Invalid mode.");

     }

+

+    Bu::sio << "read["

+        << ((iLookAheadUsed+iLookAheadStart)%iLookAheadSize)

+        << "]: "

+        << aLookAhead[(iLookAheadUsed+iLookAheadStart)%iLookAheadSize].eType;

 }

 

 Token Lexer::nextTokenNormal()

@@ -235,5 +263,11 @@ void Lexer::setRadix( int i )
 

 Token &Lexer::operator[]( int iIdx )

 {

+    while( iIdx >= iLookAheadUsed )

+    {

+        fillToken();

+        iLookAheadUsed++;

+    }

+    return aLookAhead[(iLookAheadStart+iIdx)%iLookAheadSize];

 }