-> becomes # for alt labels

tool/MIGRATION.txt

@@ -1,17 +1,23 @@
+Parsers
+
+* Full context LL(*) not SLL(*)
+* Adaptive, takes all but indirect left-recursion
+
 Actions/scopes
 
 * no global scopes. no scope[n].
 
 Trees
 
+* no ASTs
+* no tree grammars
+* parse trees created by default
 * moved methods to Trees
-* Tree->AST
-* added parse trees
-
- no -> and other tree construct in tree grammars
 
 Lexers
 
 * Added [Abc] notation
 
-* unicode rule/token names
+* unicode rule/token names
+
+* -> skip notation

tool/playground/T.g

@@ -1,8 +1,25 @@
 grammar T;
-s : e ';' ;
-e : e '*' e
-  | ID
-  | INT
-  ;
-INT : '0'..'9'+;
-WS : (' '|'\n') {skip();} ;
+@members {
+  public static class LeafListener extends TBaseListener {
+    public void exitCall(TParser.CallContext ctx) {
+      System.out.printf("%s %s",ctx.e().start.getText(),
+                ctx.eList());
+    }
+    public void exitInt(TParser.IntContext ctx) {
+      System.out.println(ctx.INT().getSymbol().getText());
+    }
+  }
+}
+s
+@init {setBuildParseTree(true);}
+@after {  System.out.println($r.ctx.toStringTree(this));  ParseTreeWalker walker = new ParseTreeWalker();
+  walker.walk(new LeafListener(), $r.ctx);}
+  : r=e ;
+e : e '(' eList ')' # Call
+  | INT             # Int
+  ;     
+eList : e (',' e)* ;
+MULT: '*' ;
+ADD : '+' ;
+INT : [0-9]+ ;
+WS : [ \t\n]+ -> skip ;

tool/src/org/antlr/v4/analysis/LeftRecursiveRuleAnalyzer.java

@@ -359,7 +359,7 @@ public class LeftRecursiveRuleAnalyzer extends LeftRecursiveRuleWalker {
 		TokenStream tokens = input.getTokenStream();
 		// find =>
 		for (int i=stop; i>=start; i--) {
-			if ( tokens.get(i).getType()==RARROW ) {
+			if ( tokens.get(i).getType()==POUND ) {
 				altAST.setTokenStopIndex(i-1);
 				return;
 			}

tool/src/org/antlr/v4/parse/ANTLRParser.g

@@ -535,7 +535,7 @@ ruleAltList
 
 labeledAlt
 	:	alternative
-		(	RARROW! id! {((AltAST)$alternative.tree).altLabel=$id.tree;}
+		(	POUND! id! {((AltAST)$alternative.tree).altLabel=$id.tree;}
 		)?
 	;
 
@@ -655,7 +655,7 @@ lexerCommandName
         :       id
         |       MODE    ->ID[$MODE]
         ;
-        
+
 altList
     :	alternative (OR alternative)* -> alternative+
     ;

tool/test/org/antlr/v4/test/TestLeftRecursion.java

@@ -252,13 +252,13 @@ public class TestLeftRecursion extends BaseTest {
 			"s : q=e {System.out.println($e.v);} ;\n" +
 			"\n" +
 			"e returns [int v]\n" +
-			"  : a=e op='*' b=e {$v = $a.v * $b.v;}  -> mult\n" +
-			"  | a=e '+' b=e {$v = $a.v + $b.v;}     -> add\n" +
-			"  | INT         {$v = $INT.int;}        -> anInt\n" +
-			"  | '(' x=e ')' {$v = $x.v;}            -> parens\n" +
-			"  | x=e '++'    {$v = $x.v+1;}          -> inc\n" +
-			"  | e '--'                              -> dec\n" +
-			"  | ID          {$v = 3;}               -> anID\n" +
+			"  : a=e op='*' b=e {$v = $a.v * $b.v;}  # mult\n" +
+			"  | a=e '+' b=e {$v = $a.v + $b.v;}     # add\n" +
+			"  | INT         {$v = $INT.int;}        # anInt\n" +
+			"  | '(' x=e ')' {$v = $x.v;}            # parens\n" +
+			"  | x=e '++'    {$v = $x.v+1;}          # inc\n" +
+			"  | e '--'                              # dec\n" +
+			"  | ID          {$v = 3;}               # anID\n" +
 			"  ; \n" +
 			"\n" +
 			"ID : 'a'..'z'+ ;\n" +
@@ -304,18 +304,18 @@ public class TestLeftRecursion extends BaseTest {
 			"// START:stat\n" +
 			"prog:   stat ;\n" +
 			"\n" +
-			"stat:   expr NEWLINE                -> printExpr\n" +
-			"    |   ID '=' expr NEWLINE         -> assign\n" +
-			"    |   NEWLINE                     -> blank\n" +
+			"stat:   expr NEWLINE                # printExpr\n" +
+			"    |   ID '=' expr NEWLINE         # assign\n" +
+			"    |   NEWLINE                     # blank\n" +
 			"    ;\n" +
 			"// END:stat\n" +
 			"\n" +
 			"// START:expr\n" +
-			"expr:   expr ('*'|'/') expr      -> MulDiv\n" +
-			"    |   expr ('+'|'-') expr      -> AddSub\n" +
-			"    |   INT                      -> int\n" +
-			"    |   ID                       -> id\n" +
-			"    |   '(' expr ')'             -> parens\n" +
+			"expr:   expr ('*'|'/') expr      # MulDiv\n" +
+			"    |   expr ('+'|'-') expr      # AddSub\n" +
+			"    |   INT                      # int\n" +
+			"    |   ID                       # id\n" +
+			"    |   '(' expr ')'             # parens\n" +
 			"    ;\n" +
 			"// END:expr\n" +
 			"\n" +

tool/test/org/antlr/v4/test/TestListeners.java

@@ -178,8 +178,8 @@ public class TestListeners extends BaseTest {
 			"  walker.walk(new LeafListener(), $r.ctx);" +
 			"}\n" +
 			"  : r=e ;\n" +
-			"e : e '(' eList ')' -> Call\n" +
-			"  | INT             -> Int\n" +
+			"e : e '(' eList ')' # Call\n" +
+			"  | INT             # Int\n" +
 			"  ;     \n" +
 			"eList : e (',' e)* ;\n" +
 			"MULT: '*' ;\n" +