Added Delete methods for slice elements to common attributes, entry, feed, person and source

commonAttributes.go

@@ -17,7 +17,7 @@ func newCommonAttributes() *CommonAttributes {
 	return new(CommonAttributes)
 }
 
-// AddAttribute adds the Attribute to the CommonAttributes.
+// AddAttribute adds the attribute to the CommonAttributes.
 func (c *CommonAttributes) AddAttribute(name, value string) {
 	if c.UndefinedAttributes == nil {
 		c.UndefinedAttributes = make([]*xml.Attr, 1)
@@ -27,6 +27,18 @@ func (c *CommonAttributes) AddAttribute(name, value string) {
 	}
 }
 
+// DeleteAttribute deletes the attribute from the CommonAttributes. It return an
+// error.
+func (c *CommonAttributes) DeleteAttribute(id int) error {
+	length := len(c.UndefinedAttributes)
+	if id > length {
+		return fmt.Errorf("error deleting undefined attribute from common attributes %v: id %v out of range %v", c, id, length)
+	}
+
+	c.UndefinedAttributes = append(c.UndefinedAttributes[:id], c.UndefinedAttributes[id+1:]...)
+	return nil
+}
+
 // Check checks the CommonAttributes for incompatibilities with RFC4287. It
 // returns an error.
 func (c *CommonAttributes) Check() error {