The methods XML::Element#add_attribute and XML::Element#set can be used to more
easily add attributes to elements. The first method simply adds an Attribute
instance and links it to the element. This allows for fine grained control over
what data the attribute should contain. The second method ("set") simply sets an
attribute based on a name and value, optionally creating the attribute if it
doesn't already exist.
This ensures that Oga can lex the following properly:
<input value="" />
Previously Ragel would stop upon finding the empty string. This was caused due
to the string rules being declared as following:
string_dquote = (dquote ^dquote+ dquote);
string_squote = (squote ^squote+ squote);
These rules only match strings _with_ content, not without. Since Ragel stops
consuming input the moment it finds unhandled data this resulted in incorrect
tokens being emitted.
Previously this wouldn't display anything due to the IO object being exhausted.
To fix this the input has to be wound back to the start, which means re-reading
it. Sadly I can't think of a way around this that doesn't require buffering
lines while parsing them (which massively increases memory usage).
The XPath number() function should also be capable of converting booleans to
numbers, something it previously was not able to do. In order to do this
reliably we can't rely on the string() function as this would make it impossible
to distinguish between literal string values and booleans. This is due to
true(), which returns a TrueClass, being converted to the string "true". This
string in turn can't be converted to a float.
When an attribute is prefixed with "xml" the default namespace should be used
automatically. This namespace is not registered on element level by default as
this namespace isn't registered manually, instead it's a "magic" namespace. This
also ensures we match the behaviour of libxml more closely, hopefully reducing
confusion.