Hey! The parser parses now! It's actually a little stupid, I didn't implement

lookahead or precedence, but I should be able to do that easily with the next
version.  I'm treating this more as a proof of concept than a real working
model.  Although it can handle +, -, (), and = :)

1 files changed, 19 insertions, 5 deletions

diff --git a/src/parser.cpp b/src/parser.cpp
index e4e8ae5..3ce73b6 100644
--- a/src/parser.cpp
+++ b/src/parser.cpp
@@ -22,16 +22,25 @@ void Bu::Parser::popLexer()
         delete sLexer.peekPop();
 }
 
+Lexer::Token *Bu::Parser::popToken()
+{
+        return sToken.peekPop();
+}
+
+void Bu::Parser::pushToken( Lexer::Token *pTok )
+{
+        sToken.push( pTok );
+}
+
 void Bu::Parser::parse()
 {
         int iCurNt = iRootNonTerminal;
         Lexer::Token *ptCur = sLexer.peek()->nextToken();
-        sio << "Token: " << sLexer.peek()->tokenToString( *ptCur ) << sio.nl;
+        sio << "Token(a): " << sLexer.peek()->tokenToString( *ptCur ) << sio.nl;
         selectProduction( iCurNt, ptCur );
         
         while( !sState.isEmpty() )
         {
-                sio << "Currently: " << *sState.peek() << sio.nl;
                 switch( (*sState.peek()).eType )
                 {
                         case State::typeTerminal:
@@ -42,7 +51,7 @@ void Bu::Parser::parse()
                                         advanceState();
                                         delete ptCur;
                                         ptCur = sLexer.peek()->nextToken();
-                                        sio << "Token: " << sLexer.peek()->tokenToString( *ptCur ) << sio.nl;
+                                        sio << "Token(b): " << sLexer.peek()->tokenToString( *ptCur ) << sio.nl;
                                 }
                                 else
                                 {
@@ -59,7 +68,7 @@ void Bu::Parser::parse()
                                         sToken.push( ptCur );
 
                                         ptCur = sLexer.peek()->nextToken();
-                                        sio << "Token: " << sLexer.peek()->tokenToString( *ptCur ) << sio.nl;
+                                        sio << "Token(c): " << sLexer.peek()->tokenToString( *ptCur ) << sio.nl;
                                 }
                                 else
                                 {
@@ -72,7 +81,7 @@ void Bu::Parser::parse()
                                         << (*sState.peek()).iIndex << sio.nl;
                                 {
                                         int iNt = (*sState.peek()).iIndex;
-                                        advanceState();
+                                        sio << "Current state: " << *sState.peek() << sio.nl;
                                         if( !selectProduction( iNt, ptCur ) )
                                         {
                                                 throw Bu::ExceptionBase("Error parsing code.");
@@ -132,7 +141,11 @@ bool Bu::Parser::selectProduction( int iNt, Lexer::Token *ptCur )
                 }
         }
         if( nt.bCanSkip )
+        {
+                sio << "Nothing matches, skipping non-terminal." << sio.nl;
+                advanceState();
                 return true;
+        }
         sio << "-->(Found nothing)" << sio.nl;
         return false;
 }
@@ -148,6 +161,7 @@ void Bu::Parser::advanceState()
                 sio.decIndent();
                 sState.pop();
                 sio << "State advanced, End of production." << sio.nl;
+                advanceState();
                 return;
         }
         sio << "State advanced, now: " << *(sState.peek()) << sio.nl;