()ef def y $-[1] 1
()ef def y $+[1] 1
*a - c - Quantifier follows nothing
-(*)b - c - Quantifier follows nothing
+(|*)b - c - Quantifier follows nothing
+(*)b - c - Unknown verb
$b b n - -
a\ - c - Search pattern not terminated
a\(b a(b y $&-$1 a(b-
'ab|cd'i ABCD y $& AB
'()ef'i DEF y $&-$1 EF-
'*a'i - c - Quantifier follows nothing
-'(*)b'i - c - Quantifier follows nothing
+'(|*)b'i - c - Quantifier follows nothing
+'(*)b'i - c - Unknown verb
'$b'i B n - -
'a\'i - c - Search pattern not terminated
'a\(b'i A(B y $&-$1 A(B-
a*(?!) aaaab n - -
-a*(?FAIL) aaaab n - -
-a*(?F) aaaab n - -
+a*(*FAIL) aaaab n - -
+a*(*F) aaaab n - -
+
+(A(A|B(*ACCEPT)|C)D)(E) AB y $1 AB
+(A(A|B(*ACCEPT)|C)D)(E) ACDE y $1$2$3 ACDCE
+
+(a)(?:(?-1)|(?+1))(b) aab y $&-$1-$2 aab-a-b
+(a)(?:(?-1)|(?+1))(b) abb y $1-$2 a-b
+(a)(?:(?-1)|(?+1))(b) acb n - -
+
+(foo)(\R1) foofoo y $1-$2 foo-foo
+(foo)(\R1)(foo)(\R1) foofoofoofoo y $1-$2-$3-$4 foo-foo-foo-foo