IsMissing function/text/sbasic/shared/03104000.xhpSun Microsystems, Inc.IsMissing functionIsMissing FunctionTests if a function is called with an optional parameter.See also: OptionalSyntax:IsMissing( ArgumentName )Parameters:ArgumentName: the name of an optional argument.If the IsMissing function is called by the ArgumentName, then True is returned.See also Examples.