public Sequence eval(StaticContext context, DocumentSet docs, Sequence contextSequence, Item contextItem) throws XPathException { if(contextItem != null)
public Sequence eval( DocumentSet docs, Sequence contextSequence, Item contextItem) throws XPathException { if (contextItem != null)
	public Sequence eval(StaticContext context, DocumentSet docs, Sequence contextSequence,		Item contextItem) throws XPathException {		if(contextItem != null)			contextSequence = contextItem.toSequence();		String strval;		return new StringValue(getArgument(0).eval(context, docs, contextSequence).getStringValue());	}