# Miscellaneous XQuery 3.0 Features

Computed namespace node constructors are supported, in the form `namespace prefix {uri-expression}` or `namespace {prefix-expression} {uri-expression}`.

In the query prolog, it is now possible to provide a default value for an external variable (for example, `declare variable $ext external := 0;`.

The "outer for" clause of a FLWOR expression is implemented. The implementation is functionally complete, but there is no optimization.

The expression `validate by type-name { expr }` is implemented.

The functions `format-date()`, `format-time()`, and `format-dateTime()`, as specified in XSLT 2.0, are now available in XPath and XQuery. (They are currently available irrespective of which version of XPath or XQuery is requested. This may change if it is deemed non-conformant.)

The function `format-number()` is now available, along with the new syntax in the Query Prolog to declare a (named or default) decimal-format.

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