X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=helm%2FDEVEL%2Fmathml_editor%2Fsrc%2FTPushLexer.cc;h=73ff25c613005785daf9d2284cf7094c9ce8b99b;hb=caab26f85122e0040555139c48a9111a0b2b9fff;hp=466ee2bd8b48c51644a4c901d16f7a178d59c15f;hpb=bf29ef82dc843dcb1929b413b36801ac26441fbd;p=helm.git

diff --git a/helm/DEVEL/mathml_editor/src/TPushLexer.cc b/helm/DEVEL/mathml_editor/src/TPushLexer.cc
index 466ee2bd8..73ff25c61 100644
--- a/helm/DEVEL/mathml_editor/src/TPushLexer.cc
+++ b/helm/DEVEL/mathml_editor/src/TPushLexer.cc
@@ -3,7 +3,7 @@
 #include "TPushLexer.hh"
 #include "APushParser.hh"
 
-TPushLexer::TPushLexer(APushParser& p) : APushLexer(p)
+TPushLexer::TPushLexer(ALogger& l, APushParser& p) : APushLexer(l, p)
 {
   state = ACCEPT;
 }
@@ -55,7 +55,6 @@ 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 if (ch == -1) ;
       else transaction(ch, ACCEPT);
       break;
@@ -65,10 +64,6 @@ TPushLexer::push(char ch)
 	  buffer.push_back(ch);
 	  state = MACRO;
 	}
-      else if (ch == '\b')
-        {
-	  state = ACCEPT;
-	}
       else if (ch == -1) error();
       else
 	{
@@ -89,11 +84,6 @@ 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 if (ch == -1)
@@ -114,7 +104,6 @@ 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 if (ch == -1) state = ACCEPT;
       else transaction(ch, ACCEPT);
       break;
@@ -133,10 +122,49 @@ TPushLexer::push(char ch)
 
   switch (state)
     {
-    case ESCAPE: parser.setCursor("\\"); break;
-    case MACRO: parser.setCursor("\\" + buffer); break;
-    case PARAMETER: parser.setCursor("#"); break;
-    default: parser.setCursor("?"); break;
+    case ESCAPE: parser.setCursorHint("\\"); break;
+    case MACRO: parser.setCursorHint("\\" + buffer); break;
+    case PARAMETER: parser.setCursorHint("#"); break;
+    default: parser.setCursorHint(""); break;
+    }
+}
+
+void
+TPushLexer::drop(bool alt)
+{
+  std::string restore = "";
+
+  switch (state)
+    {
+    case ACCEPT:
+    case IGNORE_SPACE:
+      restore = parser.drop(alt);
+      if (restore.length() > 0 && restore[0] == '\\')
+	{
+	  buffer = std::string(restore, 1, restore.length() - 1);
+	  state = (buffer.length() > 0) ? MACRO : ESCAPE;
+	}
+      break;
+    case ESCAPE:
+      state = ACCEPT;
+      break;
+    case MACRO:
+      if (alt) buffer.erase();
+      else buffer.erase(buffer.length() - 1, 1);
+      if (buffer.length() == 0) state = ESCAPE;
+      break;
+    case PARAMETER:
+    default:
+      assert(0);
+      break;
+    }
+
+  switch (state)
+    {
+    case ESCAPE: parser.setCursorHint("\\"); break;
+    case MACRO: parser.setCursorHint("\\" + buffer); break;
+    case PARAMETER: parser.setCursorHint("#"); break;
+    default: parser.setCursorHint(""); break;
     }
 }