The World WIde Web Consortium XML Query Working Group has published two First Public Working Drafts: “XQuery Scripting Extension 1.0” and “XQuery Scripting Extension 1.0 Use Cases.” The former defines an extension to XQuery 1.0 and XQuery Update facility. Expressions can be evaluated in a specific order, with later expressions seeing the effects of the expressions that came before them. This specification introduces the concept of a block with local variable declarations, as well as several new kinds of expressions, including assignment, while, continue, break, and exit expressions. The latter specification includes the usage scenarios that motivate the changes in the former. http://www.w3.org/TR/2008/WD-xquery-sx-10-20080328/. Also see https://gilbane.com/2008/03/first_public_working_draft_of/