a few simple examples

src/examples/00/modules/foo.js

@@ -1,3 +0,0 @@
-export function foo () {
-	return 42;
-}

src/examples/00/modules/main.js

@@ -1,2 +1,2 @@
-import { foo } from './foo';
-console.log( foo() );
+import { cube } from './maths.js';
+console.log( cube( 5 ) ); // 125

src/examples/00/modules/maths.js

@@ -0,0 +1,12 @@
+// This function isn't used anywhere, so
+// Rollup excludes it from the bundle...
+export function square ( x ) {
+	return x * x;
+}
+
+// This function gets included
+export function cube ( x ) {
+	// rewrite this as `square( x ) * x`
+	// and see what happens!
+	return x * x * x;
+}

src/examples/00/name

@@ -1 +1 @@
-first example
+Tree-shaking

src/examples/01/modules/answer.js

@@ -0,0 +1 @@
+export default 42;

src/examples/01/modules/lib.js

@@ -1,9 +0,0 @@
-export const sqrt = Math.sqrt;
-
-export function square( x ) {
-	return x * x;
-}
-
-export function diag ( x, y ) {
-	return sqrt( square( x ) + square( y ) );
-}

src/examples/01/modules/main.js

@@ -1,3 +1,7 @@
-import { diag } from './lib';
+import answer from './answer.js';
 
-console.log( diag( 3, 4 ) ); // 5
+// Default exports from the 'entry module' are
+// exported from the bundle
+export default function () {
+	console.log( 'the answer is ' + answer );
+}

src/examples/01/name

@@ -1 +1 @@
-second example
+Default exports

src/examples/02/modules/main.js

@@ -1,4 +1,14 @@
-import { getStringTag } from './unbind';
-import { arrayTag } from './tags';
+// There are many ways to export bindings
+// from an ES2015 module
+export var foo = 1;
 
-console.log( getStringTag( [] ) === arrayTag ); // true
+export function bar () {
+	return foo; // try changing this to `foo++`
+}
+
+function baz () {
+	return bar();
+}
+
+export { baz };
+export * from './qux';

src/examples/02/modules/qux.js

@@ -0,0 +1 @@
+export var qux = 'QUX';

src/examples/02/modules/tags.js

@@ -1,10 +0,0 @@
-// A number of StringTags.
-export const
-	arrayTag = '[object Array]',
-	dateTag = '[object Date]',
-	functionTag = '[object Function]',
-	mathTag = '[object Math]',
-	nullTag = '[object Null]',
-	regexTag = '[object RegExp]',
-	stringTag = '[object String]',
-	undefinedTag = '[object Undefined]';

src/examples/02/modules/unbind.js

@@ -1,12 +0,0 @@
-// Create functions from prototype methods, to avoid using call.
-const unbind = Function.prototype.bind.bind(Function.prototype.call);
-
-export const slice = unbind(Array.prototype.slice);
-
-// Check if the first argument has a given property name.
-export const hasOwn = unbind(Object.prototype.hasOwnProperty);
-
-// Get the string tag of an object.
-export const getStringTag = unbind(Object.prototype.toString);
-
-export default unbind;

src/examples/02/name

@@ -1 +1 @@
-deadcode-elimination
+Named exports

src/examples/03/modules/main.js

@@ -0,0 +1,5 @@
+// You can import external modules into your bundle –
+// it doesn't matter if they're ES2015 or legacy
+import $ from 'jquery';
+
+$( 'body' ).html( '<h1>Hello world!</h1>' );

src/examples/03/name

@@ -0,0 +1 @@
+External imports