diff --git a/src/lalr/ErrorCode.hpp b/src/lalr/ErrorCode.hpp
index 4ed44c3..0fcab63 100644
--- a/src/lalr/ErrorCode.hpp
+++ b/src/lalr/ErrorCode.hpp
@@ -12,6 +12,7 @@ enum ErrorCode
     PARSER_ERROR_NONE, ///< No %error.
     LALR_ERROR_SYNTAX, ///< Syntax %error occured while parsing input.
     LALR_ERROR_UNTERMINATED_LITERAL, ///< Unterminated literal in an lalr grammar.
+    LALR_ERROR_EMPTY_LITERAL, ///< Empty literal in an lalr grammar.
     LEXER_ERROR_MISSING_ACTION_HANDLER, ///< A lexer action hasn't been bound to a function.
     LEXER_ERROR_SYNTAX, ///< Syntax %error occured while parsing some input.
     LEXER_ERROR_SYMBOL_CONFLICT, ///< A lexer state matches more than one symbol.
diff --git a/src/lalr/GrammarParser.cpp b/src/lalr/GrammarParser.cpp
index 7c369f3..6564190 100644
--- a/src/lalr/GrammarParser.cpp
+++ b/src/lalr/GrammarParser.cpp
@@ -228,12 +228,21 @@ bool GrammarParser::match_literal()
         {
             escaped = *position == '\\';
             ++position;
+            if ( *position == '\\' && escaped )
+            {
+                ++position;
+                escaped = false;
+            }
         }
         if ( position == end_ || !is_new_line(position) )
         {
             lexeme_.assign( position_, position );
             position_ = position;
             expect( "'" );
+            if ( lexeme_.empty() )
+            {
+                error( LALR_ERROR_EMPTY_LITERAL, "empty literal" );
+            }
             return true;
         }
         error( LALR_ERROR_UNTERMINATED_LITERAL, "unterminated literal" );
@@ -253,10 +262,19 @@ bool GrammarParser::match_regex()
         {
             escaped = *position == '\\';
             ++position;
+            if (*position == '\\' && escaped)
+            {
+                ++position;
+                escaped = false;
+            }
         }
         lexeme_.assign( position_, position );
         position_ = position;
         expect( "\"" );
+        if ( lexeme_.empty() )
+        {
+            error( LALR_ERROR_EMPTY_LITERAL, "empty regex" );
+        }
         return true;
     }
     return false;