Associate PaperScope objects with the script tag that produced them through an assigned unique id.

src/core/PaperScope.js

@@ -24,6 +24,7 @@ var PaperScope = this.PaperScope = Base.extend({
 		this.documents = [];
 		this.tools = [];
 		this.id = id;
+		PaperScope.scopes[id] = this;
 	},
 
 	/**
@@ -41,15 +42,19 @@ var PaperScope = this.PaperScope = Base.extend({
 		}, scope);
 	},
 
-	// Methods for setting and restoring paper scopes:
-	statics: {
-		set: function(scope) {
-			this.previous = paper;
-			paper = scope;
-		},
+	remove: function() {
+		// Remove all documents and tools.
+		for (var i = this.documents.length - 1; i >= 0; i--)
+			this.documents[i].remove();
+		for (var i = this.tools.length - 1; i >= 0; i--)
+			this.tools[i].remove();
+	},
 
-		restore: function() {
-			paper = this.previous;
+	statics: {
+		scopes: {},
+
+		get: function(id) {
+			return this.scopes[id] || null;
 		}
 	}
 });

src/core/PaperScript.js

@@ -195,7 +195,8 @@ var PaperScript = this.PaperScript = new function() {
 	}
 
 	function load() {
-		var scripts = document.getElementsByTagName('script');
+		var scripts = document.getElementsByTagName('script'),
+			count = 0;
 		for (var i = 0, l = scripts.length; i < l; i++) {
 			var script = scripts[i];
 			// Only load this script if it not loaded already.
@@ -204,13 +205,22 @@ var PaperScript = this.PaperScript = new function() {
 				// Produce a new PaperScope for this script now. Scopes are
 				// cheap so let's not worry about the initial one that was
 				// already created.
-				var scope = new PaperScope(script.src || ('script-' + i));
+				// Define an id for each paperscript, so its scope can be
+				// retrieved through PaperScope.get().
+				var scope = new PaperScope(script.getAttribute('id')
+						|| script.src || ('paperscript-' + (count++)));
+				// Make sure the tag also has this id now. If it already had an
+				// id, we're not changing it, since it's the first option we're
+				// trying to get an id from above.
+				script.setAttribute('id', scope.id);
 				// If a canvas id is provided, create a document for it now,
 				// so the active document is defined.
 				var canvas = script.getAttribute('canvas');
 				if (canvas = canvas && document.getElementById(canvas)) {
 					// Create a Document for this canvas, using the right scope
 					paper = scope;
+					// XXX: Do not pass canvas to Document.
+					// Create DocumentView here instead.
 					new Document(canvas);
 				}
 				if (script.src) {

src/document/Document.js

@@ -78,8 +78,7 @@ var Document = this.Document = Base.extend({
 	remove: function() {
 		var res = Base.splice(this._scope.documents, null, this._index, 1);
 		this._scope = null;
-		// Remove all views. This also removes the event handlers installed for
-		// then.
+		// Remove all views. This also removes the installed event handlers.
 		for (var i = this.views.length - 1; i >= 0; i--)
 			this.views[i].remove();
 		return !!res.length;