Returns true if a call to unparsed-text would succeed with identical arguments.
|$href||The $href is a string containing a URI reference. It must identify a resource that can be read as text. If the URI is a relative URI then it is resolved relative to the base URI from the static context.|
|$encoding||If $encoding parameter is present and the URI points to a "text" file, the encoding is ignored since all the files are in UTF-8 in the database. However, if the URI points to a binary file, then an attempt will be made to convert it to the specified encoding and if the conversion succeeds it returns true. If the conversion fails, an exception is returned. The $encoding parameter must be passed when the URI resolves to a binary resource.|
fn.unparsedTextAvailable("http://marklogic.com/test.xml","UTF-8"); => true if the document is available as unparsed text