exprSingle throws XPathException
:
	( ( "for" | "let" ) DOLLAR ) => flworExpr
	| ( ( "some" | "every" ) DOLLAR ) => quantifiedExpr
	| ( "if" LPAREN ) => ifExpr 
	| ( "typeswitch" LPAREN ) => typeswitchExpr
	| ( "update" ( "replace" | "value" | "insert" | "delete" | "rename" | "batch start" | "batch finish")) => updateExpr
	| orExpr
	;

// === Xupdate ===

updateExpr throws XPathException
:
	"update"^
	(
		replaceExpr
		| valueExpr
		| insertExpr
		| deleteExpr
		| ( "rename" . "as" ) => renameExpr
		| batchStartExpr
		| batchFinishExpr
	)	
	;