Allows non-array, non-string values to be node.class values.

`node.class` is always an array, so if we're a string, we split on spaces, like
how classes are specified when creating HTML strings, or if we're a non-array,
non-string value, we wrap ourselves into single-element array.

Includes the following patch-level changes:
	- Moves the location of the `isBooleanAttribute` function.

This is a minor change.

lib/index.js

@@ -123,8 +123,14 @@ function parseAttributes(attributes) {
 			}
 		});
 
-		if (!Array.isArray(nodeAttributes.class)) {
+		// `node.class` is always an array, so if we're a string, we
+		// split on spaces, like how classes are specified when
+		// creating HTML strings, or if we're a non-array, non-string
+		// value, we wrap ourselves into single-element array.
+		if (isString(nodeAttributes.class)) {
 			nodeAttributes.class = nodeAttributes.class.split(' ');
+		} else if (!Array.isArray(nodeAttributes.class)) {
+			nodeAttributes.class = [nodeAttributes.class];
 		}
 
 	}
@@ -289,6 +295,11 @@ function htmlEscape(content) {
 	});
 }
 
+// https://github.com/kangax/html-minifier/issues/63#issuecomment-37763316
+function isBooleanAttribute(attribute) {
+    return (/^(?:allowfullscreen|async|autofocus|autoplay|checked|compact|controls|declare|default|defaultchecked|defaultmuted|defaultselected|defer|disabled|draggable|enabled|formnovalidate|hidden|indeterminate|inert|ismap|itemscope|loop|multiple|muted|nohref|noresize|noshade|novalidate|nowrap|open|pauseonexit|readonly|required|reversed|scoped|seamless|selected|sortable|spellcheck|translate|truespeed|typemustmatch|visible)$/i).test(attribute);
+}
+
 /* Renders a singleton attribute key, or a key-value attribute pair,
  * HTML-escaping the value. */
 function renderAttribute(key, value) {
@@ -303,11 +314,6 @@ function renderAttribute(key, value) {
 	}
 }
 
-// https://github.com/kangax/html-minifier/issues/63#issuecomment-37763316
-function isBooleanAttribute(attribute) {
-    return (/^(?:allowfullscreen|async|autofocus|autoplay|checked|compact|controls|declare|default|defaultchecked|defaultmuted|defaultselected|defer|disabled|draggable|enabled|formnovalidate|hidden|indeterminate|inert|ismap|itemscope|loop|multiple|muted|nohref|noresize|noshade|novalidate|nowrap|open|pauseonexit|readonly|required|reversed|scoped|seamless|selected|sortable|spellcheck|translate|truespeed|typemustmatch|visible)$/i).test(attribute);
-}
-
 function renderStyle(style) {
 	return Object.keys(style).reduce(function styler(styleString, property) {
 		return styleString + property + ':' + style[property] + ';';

package.json

@@ -1,6 +1,6 @@
 {
   "name": "lmth",
-  "version": "6.1.0",
+  "version": "6.2.0",
   "description": "A \"type-safe\" HTML DSL for JavaScript environments.",
   "main": "lib/index.js",
   "scripts": {