<?xml version="1.0" encoding="iso-8859-1"?> <?xml-stylesheet href="../../make-menu.xsl" type="text/xsl"?><html> <head> <this-is section="changes" page="intro92" subpage="xquery1192"/> <!-- Generated at 2011-12-09T20:47:22.916Z--><title>Saxonica: XSLT and XQuery Processing: XQuery 1.1</title> <meta name="coverage" content="Worldwide"/> <meta name="copyright" content="Copyright Saxonica Ltd"/> <meta name="title" content="Saxonica: XSLT and XQuery Processing: XQuery 1.1"/> <meta name="robots" content="noindex,nofollow"/> <link rel="stylesheet" href="../../saxondocs.css" type="text/css"/> </head> <body class="main"> <h1>XQuery 1.1</h1> <p>These new features are available only with Saxon-PE or Saxon-EE, and require XQuery 1.1 to be enabled (a) from the command line (-qversion:1.1) or Configuration and (b) from the query prolog (<code>xquery version "1.1";</code>).</p> <p>The try/catch syntax from the draft XQuery 1.1 specification is implemented, but without the ability to declare variables to receive error information. This feature cannot be used with XQuery Updates.</p> <p>A subset of the grouping syntax from the draft XQuery 1.1 specification is implemented. The <code>group by</code> clause must be preceded in the FLWOR expression by (a) a single <code>for</code> clause, which selects the sequence to be grouped, and (b) a single <code>let</code> clause, which defines the grouping key; the "group by" clause must name the variable that is declared in the <code>let</code> clause. For example: <code>for $x in //employee let $k := $x/department group by $k return ...</code>. Within the <code>return</code> clause, <code>$x</code> refers to the content of the current group, and <code>$k</code> to the current grouping key.</p> <p>The "outer for" clause of a FLWOR expression is implemented. The implementation is functionally complete, but there is no optimization.</p> <p>Computed namespace node constructors are supported, in the form <code>namespace prefix {uri-expression}</code> or <code>namespace {prefix-expression} {uri-expression}</code>.</p> <p>In the query prolog, it is now possible to provide a default value for an external variable (for example, <code>declare variable $ext external := 0;</code>.</p> <p>The <code>declare context item</code> declaration in the query prolog is implemented. This allows a required type and a default value to be declared for the context item. At present (the rules aren't entirely clear) it is possible to specify a value from the calling API, or to not specify a value, regardless whether "external" is specified or not. At present there is no interaction with the API facilities for defining a required type for the context item: both can be used independently.</p> <p>The expression <code>validate as type-name { expr }</code> is implemented.</p> <p>The functions <code>format-date()</code>, <code>format-time()</code>, and <code>format-dateTime()</code>, as specified in XSLT 2.0, are now also available in XQuery 1.1. </p> <p>The function <code>format-number()</code> is now available, along with the new syntax in the Query Prolog to declare a (named or default) decimal-format. (This has entailed some internal change in the way decimal formats are managed, since XQuery allows each module to have its own set of named decimal formats.)</p> <p class="subhead">Higher-order functions</p> <p>The new facility for higher-order functions is fully implemented, with one or two restrictions.</p> <p>The syntax <code>my:function#3</code> is now available. This is synonymous with the extension available in earlier releases, <code>saxon:function('my:function', 3)</code>. This has also been extended so that it works with all functions; the Saxon extension previously worked only with user-written functions.</p> <p>The <code>SequenceType</code> syntax <code>function()</code> is now available to denote the type of a function item, that is, the type of the result of <code>my:function#3</code> or <code>saxon:function('my:function', 3)</code>. You can also use a full type signature, for example <code>function(xs:int, xs:int) as xs:string*</code>.</p> <p>The type <code>function()</code> is implemented as a new subtype of <code>Item</code> represented by the Java class <code>net.sf.saxon.om.FunctionItem</code>. Note that any code that assumes every Item is either a node or an atomic value is potentially affected.</p> <p>Dynamic function calls can now be written, for example, as <code>$f(x, y)</code> rather than <code>saxon:call($f, x, y)</code> as previously. In this expression <code>$f</code> can be replaced by any primary expression or filter expression whose value is a function item.</p> <p>Inline (anonymous) functions can be written, for example <code>function ($x as xs:integer) as xs:boolean {$x mod 2 eq 0}</code>. Such a function will typically be used as an argument in a function call expecting a parameter of type <code>function()</code>.</p> <p>The functions <code>fn:function-name()</code>, <code>fn:function-arity()</code>, and <code>fn:partial-apply()</code> are implemented.</p> <p>Saxon applies function coercion when a function is passed to another function, or when it is returned as a function result. However it also implements a proposed change to the specification whereby function coercion is not used for operations such as "instance of". These follow stricter type checking rules: a function <code>F(A,B)->T</code> is an instance of a type <code>F(X,Y)->U</code> if every T is an instance of U, every X is an instance of A, and every Y is an instance of B.</p> <table width="100%"> <tr> <td> <p align="right"><a class="nav" href="xsd92.xml">Next</a></p> </td> </tr> </table> </body> </html>