public void AddExtension(Selector selector, Extend extends, Env env)
{
foreach (var extending in extends.Exact)
{
Extender match = null;
if ((match = _extensions.OfType <ExactExtender>().FirstOrDefault(e => e.BaseSelector.ToString().Trim() == extending.ToString().Trim())) == null)
{
match = new ExactExtender(extending, extends);
_extensions.Add(match);
}
match.AddExtension(selector, env);
}
foreach (var extending in extends.Partial)
{
Extender match = null;
if ((match = _extensions.OfType <PartialExtender>().FirstOrDefault(e => e.BaseSelector.ToString().Trim() == extending.ToString().Trim())) == null)
{
match = new PartialExtender(extending, extends);
_extensions.Add(match);
}
match.AddExtension(selector, env);
}
if (Parent != null)
{
Parent.AddExtension(selector, extends, env);
}
}
/// <summary>
/// Tests whether or not this extender matches the selector elements in <paramref name="list"/>
/// by checking if the elements in <see cref="Extender.BaseSelector"/> are a subsequence of the ones in
/// <paramref name="list"/>.
///
/// The special case in the comparison is that if the subsequence element we are comparing is the last one in its
/// sequence, we don't compare combinators.
///
/// A practical example of why we do that is an extendee with the selector:
///
/// .test .a
///
/// and an extender with the selector
///
/// .test
///
/// The extender should match, even though the .test element in the extendee will have the descendant combinator " "
/// and the .test element in the extender won't.
/// </summary>
private static bool ElementListMatches(this PartialExtender extender, IList <Element> list)
{
int count = extender.BaseSelector.Elements.Count;
return(extender.BaseSelector.Elements.IsSubsequenceOf(list, (subIndex, subElement, index, seqelement) => {
if (subIndex < count - 1)
{
return Equals(subElement.Combinator, seqelement.Combinator) &&
string.Equals(subElement.Value, seqelement.Value) &&
Equals(subElement.NodeValue, seqelement.NodeValue);
}
return string.Equals(subElement.Value, seqelement.Value) &&
Equals(subElement.NodeValue, seqelement.NodeValue);
}));
}