A first partial implementation of deleting is introduced. The user might

[helm.git] / helm / DEVEL / mathml_editor / src / TPushLexer.cc

diff --git a/helm/DEVEL/mathml_editor/src/TPushLexer.cc b/helm/DEVEL/mathml_editor/src/TPushLexer.cc
index b943877870c0400a8c42f94d469feab5fbe8f4f2..4b24523da5e494c01ac2202bfbea438063fbf996 100644 (file)
--- a/helm/DEVEL/mathml_editor/src/TPushLexer.cc
+++ b/helm/DEVEL/mathml_editor/src/TPushLexer.cc
@@ -31,7 +31,7 @@ TPushLexer::transaction(char ch, State newState)
     case '\t':
     case ' ': parser.push(TToken(TToken::SPACE, ch)); break;
     case '~': parser.push(TToken(TToken::ACTIVE, ch)); break;
-    case '%': parser.push(TToken(TToken::COMMENT)); break;
+    case '%': parser.push(TToken(TToken::COMMENT)); break;     
     default:
       if (isalpha(ch)) parser.push(TToken(TToken::LETTER, ch));
       else if (isdigit(ch)) parser.push(TToken(TToken::DIGIT, ch));
@@ -49,6 +49,7 @@ TPushLexer::push(char ch)
     case ACCEPT:
       if (ch == '\\') state = ESCAPE;
       else if (ch == '#') state = PARAMETER;
+      else if (ch == '\b') parser.push(TToken(TToken::GDELETE));
       else transaction(ch, ACCEPT);
       break;
     case ESCAPE:
@@ -57,6 +58,10 @@ TPushLexer::push(char ch)
          buffer.push_back(ch);
          state = MACRO;
        }
+      else if (ch == '\b')
+        {
+         state = ACCEPT;
+       }
       else
        {
          parser.push(TToken(TToken::CONTROL, ch));
@@ -76,6 +81,11 @@ TPushLexer::push(char ch)
          buffer.erase();
          state = PARAMETER;
        }
+      else if (ch == '\b')
+       {
+         buffer.erase(buffer.length() - 1, 1);
+         if (buffer.length() == 0) state = ESCAPE;
+       }
       else if (isalpha(ch))
        buffer.push_back(ch);
       else
@@ -90,6 +100,7 @@ TPushLexer::push(char ch)
       if (ch == '\\') state = ESCAPE;
       else if (ch == '#') state = PARAMETER;
       else if (isspace(ch)) ;
+      else if (ch == '\b') parser.push(TToken(TToken::GDELETE));
       else transaction(ch, ACCEPT);
       break;
     case PARAMETER: