amberc.js: more documentation for createConcatenator()

bin/amberc.js

@@ -59,9 +59,25 @@ function always_resolve(callback) {
 function createConcatenator () {
 	var defineAmdDefine = function () {
 		var path = require('path');
-		return ($SRC$)(module);
+		return ($AMDEFINE_SRC$)(module);
 	};
 
+	// The createAmdefineString is hack to help injecting amdefine into the concatenated output.
+	//
+	// Usually, the line 'var define = require('amdefine')(module), requirejs = define.require;'
+	// is needed when using amdefine with node and npm installed.
+	// var f = require('amdefine') itself returns one big self-sufficient function which must be called
+	// as f(module) to get the define you can use.
+	//
+	// However, amdefine needs the definition of the 'path' variable (node's internal 'path' module).
+	// To create this dependency the defineAmdDefine() function is used which defines
+	// the path variable first and adds a placeholder for the amdefine function/sourcecode.
+	// The defineAmdDefine() function is then converted to its string representation
+	// and the placeholder is replaced with the actual sourcecode of the amdefine function.
+	var createAmdefineString = function() {
+		return ('' + defineAmdDefine).replace('$AMDEFINE_SRC$', '' + require('amdefine'));
+	}
+
 	return {
 		elements: [],
 		ids: [],
@@ -76,7 +92,7 @@ function createConcatenator () {
 		},
 		start: function () {
 			this.add(
-				'var define = (' + ('' + defineAmdDefine).replace('$SRC$', '' + require('amdefine')) + ')(), requirejs = define.require;',
+				'var define = (' + createAmdefineString() + ')(), requirejs = define.require;',
 				'define("amber_vm/browser-compatibility", [], {});'
 			);
 		},