diff --git a/examples/network/github_timeline.own b/examples/network/github_timeline.own
index 2363f3b..b04c2c2 100644
--- a/examples/network/github_timeline.own
+++ b/examples/network/github_timeline.own
@@ -28,13 +28,11 @@ def show_github_events(event) {
 
 def github_event_type(event) {
     type = event["type"]
-    repo = event["repo"]
-    repo = "https://github.com/" + repo["name"]
+    repo = "https://github.com/" + event["repo"]["name"]
     payload = event["payload"]
     
     if (type == "CommitCommentEvent") {
-      comment = payload["comment"]
-      return "commented commit in " + repo + "\n" + comment["body"]
+      return "commented commit in " + repo + "\n" + payload["comment"]["body"]
     }
     if (type == "CreateEvent") {
       return "created " + payload["ref_type"] + " on " + repo
@@ -46,13 +44,10 @@ def github_event_type(event) {
       return "forked repository " + repo
     }
     if (type == "IssueCommentEvent") {
-      comment = payload["comment"]
-      issue = payload["issue"]
-      return "commented issue " + issue["title"] + " on " + repo + "\n" + comment["body"]
+      return "commented issue " + payload["issue"]["title"] + " on " + repo + "\n" + payload["comment"]["body"]
     }
     if (type == "IssuesEvent") {
-      issue = payload["issue"]
-      return payload["action"] + " issue '" + issue["title"] + "' on " + repo
+      return payload["action"] + " issue '" + payload["issue"]["title"] + "' on " + repo
     }
     if (type == "PullRequestEvent") {
       pr = payload["pull_request"]
diff --git a/src/com/annimon/ownlang/parser/Parser.java b/src/com/annimon/ownlang/parser/Parser.java
index 4d6403a..9608ebf 100644
--- a/src/com/annimon/ownlang/parser/Parser.java
+++ b/src/com/annimon/ownlang/parser/Parser.java
@@ -172,6 +172,7 @@ public final class Parser {
     }
     
     private FunctionDefineStatement functionDefine() {
+        // def name(arg1, arg2) { ... }  ||  def name(args) = expr
         final String name = consume(TokenType.WORD).getText();
         consume(TokenType.LPAREN);
         final List<String> argNames = new ArrayList<>();
@@ -188,6 +189,7 @@ public final class Parser {
     }
     
     private FunctionalExpression function() {
+        // function(arg1, arg2, ...)
         final String name = consume(TokenType.WORD).getText();
         consume(TokenType.LPAREN);
         final FunctionalExpression function = new FunctionalExpression(name);
@@ -199,6 +201,7 @@ public final class Parser {
     }
     
     private Expression array() {
+        // [value1, value2, ...]
         consume(TokenType.LBRACKET);
         final List<Expression> elements = new ArrayList<>();
         while (!match(TokenType.RBRACKET)) {
@@ -209,6 +212,7 @@ public final class Parser {
     }
     
     private Expression map() {
+        // {key1 : value1, key2 : value2, ...}
         consume(TokenType.LBRACE);
         final Map<Expression, Expression> elements = new HashMap<>();
         while (!match(TokenType.RBRACE)) {
@@ -222,6 +226,7 @@ public final class Parser {
     }
     
     private ArrayAccessExpression element() {
+        // array[e1][e2]...[eN]
         final String variable = consume(TokenType.WORD).getText();
         final List<Expression> indices = new ArrayList<>();
         do {
diff --git a/src/com/annimon/ownlang/parser/ast/ArrayAccessExpression.java b/src/com/annimon/ownlang/parser/ast/ArrayAccessExpression.java
index 45f65c4..e5dfff8 100644
--- a/src/com/annimon/ownlang/parser/ast/ArrayAccessExpression.java
+++ b/src/com/annimon/ownlang/parser/ast/ArrayAccessExpression.java
@@ -1,10 +1,6 @@
 package com.annimon.ownlang.parser.ast;
 
-import com.annimon.ownlang.lib.ArrayValue;
-import com.annimon.ownlang.lib.MapValue;
-import com.annimon.ownlang.lib.Types;
-import com.annimon.ownlang.lib.Value;
-import com.annimon.ownlang.lib.Variables;
+import com.annimon.ownlang.lib.*;
 import java.util.List;
 
 /**
@@ -25,26 +21,37 @@ public final class ArrayAccessExpression implements Expression {
     public Value eval() {
         Value container = Variables.get(variable);
         if (container.type() == Types.ARRAY) {
-            return getArray().get(lastIndex());
+            final int lastIndex = (int) lastIndex().asNumber();
+            return getArray().get(lastIndex);
         }
-        return consumeMap(container).get(indices.get(0).eval());
+        return getMap().get(lastIndex());
     }
     
     public ArrayValue getArray() {
         ArrayValue array = consumeArray(Variables.get(variable));
         final int last = indices.size() - 1;
         for (int i = 0; i < last; i++) {
-            array = consumeArray( array.get(index(i)) );
+            final int index = (int) index(i).asNumber();
+            array = consumeArray( array.get(index) );
         }
         return array;
     }
     
-    public int lastIndex() {
+    public MapValue getMap() {
+        MapValue map = consumeMap(Variables.get(variable));
+        final int last = indices.size() - 1;
+        for (int i = 0; i < last; i++) {
+            map = consumeMap( map.get(index(i)) );
+        }
+        return map;
+    }
+    
+    public Value lastIndex() {
         return index(indices.size() - 1);
     }
     
-    private int index(int index) {
-        return (int) indices.get(index).eval().asNumber();
+    private Value index(int index) {
+        return indices.get(index).eval();
     }
     
     private ArrayValue consumeArray(Value value) {
diff --git a/src/com/annimon/ownlang/parser/ast/ArrayAssignmentStatement.java b/src/com/annimon/ownlang/parser/ast/ArrayAssignmentStatement.java
index b2222ac..d39b7f6 100644
--- a/src/com/annimon/ownlang/parser/ast/ArrayAssignmentStatement.java
+++ b/src/com/annimon/ownlang/parser/ast/ArrayAssignmentStatement.java
@@ -22,10 +22,11 @@ public final class ArrayAssignmentStatement implements Statement {
     public void execute() {
         final Value container = Variables.get(array.variable);
         if (container.type() == Types.ARRAY) {
-            array.getArray().set(array.lastIndex(), expression.eval());
+            final int lastIndex = (int) array.lastIndex().asNumber();
+            array.getArray().set(lastIndex, expression.eval());
             return;
         }
-        array.consumeMap(container).set(array.indices.get(0).eval(), expression.eval());
+        array.getMap().set(array.lastIndex(), expression.eval());
     }
     
     @Override