5.3.1.4 Function Type Declarations

 function-type = "as" type-expression [array-designator] 
 array-designator = "(" ")"  

Static Semantics

§ The specified type of a <function-type> that does not include an <array-designator> element is the declared type referenced by its <type-expression> element.

§ The specified type of a <function-type> that includes an <array-designator> element is resizable array with a declared element type that is the declared type referenced by its <type-expression> element.