diff --git a/python/src/com/jetbrains/python/parsing/FunctionParsing.java b/python/src/com/jetbrains/python/parsing/FunctionParsing.java
index 7e93ab69827a..90ad2ad74b42 100644
--- a/python/src/com/jetbrains/python/parsing/FunctionParsing.java
+++ b/python/src/com/jetbrains/python/parsing/FunctionParsing.java
@@ -97,7 +97,7 @@ public class FunctionParsing extends Parsing {
           builder.advanceLexer();
         }
         else if (builder.getTokenType() == PyTokenTypes.LPAR) {
-          parseParameterSubList(builder);
+          parseParameterSubList();
         }
         else {
           builder.error(", or ( or ) expected");
@@ -132,27 +132,27 @@ public class FunctionParsing extends Parsing {
     parameterList.done(PyElementTypes.PARAMETER_LIST);
   }
 
-  private void parseParameterSubList(PsiBuilder builder) {
-    LOG.assertTrue(builder.getTokenType() == PyTokenTypes.LPAR);
-    builder.advanceLexer();
+  private void parseParameterSubList() {
+    assertCurrentToken(PyTokenTypes.LPAR);
+    myBuilder.advanceLexer();
     while (true) {
-      if (builder.getTokenType() == PyTokenTypes.IDENTIFIER) {
-        final PsiBuilder.Marker parameter = builder.mark();
-        builder.advanceLexer();
+      if (myBuilder.getTokenType() == PyTokenTypes.IDENTIFIER) {
+        final PsiBuilder.Marker parameter = myBuilder.mark();
+        myBuilder.advanceLexer();
         parameter.done(PyElementTypes.FORMAL_PARAMETER);
       }
-      else if (builder.getTokenType() == PyTokenTypes.LPAR) {
-        parseParameterSubList(builder);
+      else if (myBuilder.getTokenType() == PyTokenTypes.LPAR) {
+        parseParameterSubList();
       }
-      if (builder.getTokenType() == PyTokenTypes.RPAR) {
-        builder.advanceLexer();
+      if (myBuilder.getTokenType() == PyTokenTypes.RPAR) {
+        myBuilder.advanceLexer();
         break;
       }
-      if (builder.getTokenType() != PyTokenTypes.COMMA) {
-        builder.error(", or ( or ) expected");
+      if (myBuilder.getTokenType() != PyTokenTypes.COMMA) {
+        myBuilder.error(", or ( or ) expected");
         break;
       }
-      builder.advanceLexer();
+      myBuilder.advanceLexer();
     }
   }
 }
diff --git a/python/src/com/jetbrains/python/parsing/Parsing.java b/python/src/com/jetbrains/python/parsing/Parsing.java
index 11b8f0cd470c..8daea27a6807 100644
--- a/python/src/com/jetbrains/python/parsing/Parsing.java
+++ b/python/src/com/jetbrains/python/parsing/Parsing.java
@@ -31,10 +31,12 @@ import com.jetbrains.python.psi.PyElementType;
  */
 public class Parsing {
   protected ParsingContext myContext;
+  protected PsiBuilder myBuilder;
   private static final Logger LOG = Logger.getInstance("#com.jetbrains.python.parsing.Parsing");
 
   protected Parsing(ParsingContext context) {
     myContext = context;
+    myBuilder = context.getBuilder();
   }
 
   public ParsingContext getParsingContext() {
@@ -54,12 +56,11 @@ public class Parsing {
   }
 
   protected void checkMatches(final IElementType token, final String message) {
-    PsiBuilder builder = myContext.getBuilder();
-    if (builder.getTokenType() == token) {
-      builder.advanceLexer();
+    if (myBuilder.getTokenType() == token) {
+      myBuilder.advanceLexer();
     }
     else {
-      builder.error(message);
+      myBuilder.error(message);
     }
   }
 
@@ -73,6 +74,6 @@ public class Parsing {
   }
 
   protected void assertCurrentToken(final PyElementType tokenType) {
-    LOG.assertTrue(myContext.getBuilder().getTokenType() == tokenType);
+    LOG.assertTrue(myBuilder.getTokenType() == tokenType);
   }
 }