1 files changed, 45 insertions, 0 deletions
diff --git a/dom/css_class.go b/dom/css_class.go
new file mode 100644
index 0000000..998dd50
--- /dev/null
+++ b/dom/css_class.go
@@ -0,0 +1,45 @@
+package dom
+
+import "strings"
+
+type ClassList map[string]struct{}
+
+func (cl ClassList) set(e Element) Element {
+	if len(cl) == 0 {
+		return e
+	}
+	classes := ""
+	for k := range cl {
+		classes += k + " "
+	}
+	classes = strings.TrimSpace(classes)
+	return e.SetAttribute("class", classes)
+}
+
+func (cl ClassList) Has(v string) bool {
+	_, ok := cl[v]
+	return ok
+}
+
+func (cl ClassList) Add(v string) ClassList {
+	cl[v] = struct{}{}
+	return cl
+}
+
+func (cl ClassList) Remove(v string) ClassList {
+	delete(cl, v)
+	return cl
+}
+
+func (cl ClassList) Toggle(v string) ClassList {
+	if cl.Has(v) {
+		cl.Remove(v)
+	} else {
+		cl.Add(v)
+	}
+	return cl
+}
+
+func NewClassList() ClassList {
+	return ClassList(make(map[string]struct{}))
+}