diff --git a/tool/playground/AA.g b/tool/playground/AA.g
index da3fb75fe..bb22bf9b2 100644
--- a/tool/playground/AA.g
+++ b/tool/playground/AA.g
@@ -23,4 +23,4 @@ expr:   INT
 
 ID  :   ('a'..'z'|'A'..'Z')+ ;
 INT :   '0'..'9'+ ;
-WS  :   (' '|'\t'|'\n'|'\r')+ {$channel=HIDDEN;} ;
+WS  :   (' '|'\t'|'\n'|'\r')+ {setChannel(HIDDEN);} ;
diff --git a/tool/playground/Fuzzy-input b/tool/playground/Fuzzy-input
deleted file mode 100644
index 321b51018..000000000
--- a/tool/playground/Fuzzy-input
+++ /dev/null
@@ -1 +0,0 @@
-a = b;
diff --git a/tool/playground/Fuzzy.g4 b/tool/playground/Fuzzy.g4
deleted file mode 100644
index a9c1ba601..000000000
--- a/tool/playground/Fuzzy.g4
+++ /dev/null
@@ -1,10 +0,0 @@
-grammar Fuzzy;
-
-options { tokenVocab=JavaLR; }
-
-scan: (pattern|.)* EOF ;
-
-pattern
-	:	a=Identifier '=' b=Identifier ';'
-		{System.out.printf("assign %s=%s", $a.text, $b.text);}
-	;
diff --git a/tool/playground/JavaLexer.g b/tool/playground/JavaLexer.g
index ec88e509a..46a4963ad 100644
--- a/tool/playground/JavaLexer.g
+++ b/tool/playground/JavaLexer.g
@@ -141,10 +141,10 @@ fragment
 UnicodeEscape
     :   '\\' 'u' HexDigit HexDigit HexDigit HexDigit
     ;// $ANTLR src "JavaCombined.g" 963
-ENUM:   'enum' {if (!enumIsKeyword) $type=Identifier;}
+ENUM:   'enum' {if (!enumIsKeyword) setType(Identifier);}
     ;// $ANTLR src "JavaCombined.g" 966
 ASSERT
-    :   'assert' {if (!assertIsKeyword) $type=Identifier;}
+    :   'assert' {if (!assertIsKeyword) setType(Identifier);}
     ;// $ANTLR src "JavaCombined.g" 970
 Identifier
     :   Letter (Letter|JavaIDDigit)*
diff --git a/tool/playground/T.g b/tool/playground/T.g
index 3cf82b68e..03d4c1128 100644
--- a/tool/playground/T.g
+++ b/tool/playground/T.g
@@ -1,4 +1,5 @@
 grammar T;
+options {k=3;}
 s : ID ;
 ID : 'a'..'z'+ ;
 WS : (' '|'\n') {skip();} ;