Update the-super-tiny-compiler.js

Plural "node"

README.md

@@ -1,4 +1,4 @@
-<a href="the-super-tiny-compiler.js"><img width="731" alt="THE SUPER TINY COMPILER" src="https://cloud.githubusercontent.com/assets/952783/14171276/ed7bf716-f6e6-11e5-96df-80a031c2769d.png"/></a>
+[![The Super Tiny Compiler](https://cloud.githubusercontent.com/assets/952783/21579290/5755288a-cf75-11e6-90e0-029529a44a38.png)](the-super-tiny-compiler.js)
 
 ***Welcome to The Super Tiny Compiler!***
 
@@ -10,6 +10,8 @@ work from end to end.
 
 ### [Want to jump into the code? Click here](the-super-tiny-compiler.js)
 
+### [You can also check it out on Glitch](https://the-super-tiny-compiler.glitch.me/)
+
 ---
 
 ### Why should I care?
@@ -32,10 +34,7 @@ file.
 
 ### I'm back, that didn't make sense
 
-Ouch, I'm really sorry. I'm planning on doing a lot more work on this to add
-inline annotations. If you want to come back when that's done, you can either
-watch/star this repo or follow me on
-[twitter](https://twitter.com/thejameskyle) for updates.
+Ouch, I'm really sorry. Let me know how it can be improved.
 
 ### Tests
 

test.js

@@ -4,7 +4,7 @@ const {
   transformer,
   codeGenerator,
   compiler,
-} = require('./super-tiny-compiler');
+} = require('./the-super-tiny-compiler');
 const assert = require('assert');
 
 const input  = '(add 2 (subtract 4 2))';

the-super-tiny-compiler.js

@@ -259,7 +259,7 @@
  *
  * If we were manipulating this AST directly, instead of creating a separate AST,
  * we would likely introduce all sorts of abstractions here. But just visiting
- * each node in the tree is enough.
+ * each node in the tree is enough for what we're trying to do.
  *
  * The reason I use the word "visiting" is because there is this pattern of how
  * to represent operations on elements of an object structure.
@@ -275,8 +275,8 @@
  *     CallExpression() {},
  *   };
  *
- * When we traverse our AST we will call the methods on this visitor whenever we
- * encounter a node of a matching type.
+ * When we traverse our AST, we will call the methods on this visitor whenever we
+ * "enter" a node of a matching type.
  *
  * In order to make this useful we will also pass the node and a reference to
  * the parent node.
@@ -286,10 +286,8 @@
  *     CallExpression(node, parent) {},
  *   };
  *
- * We call these functions when we "enter" the node. But there is also the
- * possibilty of calling things on "exit".
- *
- * Imagine our tree structure from before in list form:
+ * However, there also exists the possibility of calling things on "exit". Imagine
+ * our tree structure from before in list form:
  *
  *   - Program
  *     - CallExpression
@@ -315,7 +313,7 @@
  *     <- CallExpression (exit)
  *   <- Program (exit)
  *
- * In order to supper that, our visitors will look like this:
+ * In order to support that, the final form of our visitor will look like this:
  *
  *   var visitor = {
  *     NumberLiteral: {
@@ -335,7 +333,7 @@
  *
  * Code generators work several different ways, some compilers will reuse the
  * tokens from earlier, others will have created a separate representation of
- * the code so that they can print node linearly, but from what I can tell most
+ * the code so that they can print nodes linearly, but from what I can tell most
  * will use the same AST we just created, which is what we’re going to focus on.
  *
  * Effectively our code generator will know how to “print” all of the different
@@ -711,16 +709,31 @@ function parser(tokens) {
  * encounter a node with a matching type.
  *
  *   traverse(ast, {
- *     Program(node, parent) {
- *       // ...
+ *     Program: {
+ *       enter(node, parent) {
+ *         // ...
+ *       },
+ *       exit(node, parent) {
+ *         // ...
+ *       },
  *     },
  *
- *     CallExpression(node, parent) {
- *       // ...
+ *     CallExpression: {
+ *       enter(node, parent) {
+ *         // ...
+ *       },
+ *       exit(node, parent) {
+ *         // ...
+ *       },
  *     },
  *
- *     NumberLiteral(node, parent) {
- *       // ...
+ *     NumberLiteral: {
+ *       enter(node, parent) {
+ *         // ...
+ *       },
+ *       exit(node, parent) {
+ *         // ...
+ *       },
  *     },
  *   });
  */