<abstract-declarator> ::= <declarator>$[\epsilon, \mbox{@<argument-list>}]$
-<argument-declarator> ::= <declarator>$[\mbox{@<identifier> @! $\epsilon$}]$
-
<argument-declarator> ::=
<declarator>$[\mbox{@<identifier> @! $\epsilon$}, \mbox{@<argument-list>}]$