()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-
^(??{q(.+)})\x{100} \x{100}\x{100} y $& \x{100}\x{100}
^(??{q(.)})\x{100} \x{100}\x{100} y $& \x{100}\x{100}
^(??{chr 0x100})\xbb \x{100}\x{bb} y $& \x{100}\x{bb}
+\x{100}?(??{""})xxx xxx y $& xxx
^(.)(??{"(.)(.)"})(.)$ abcd y $1-$2 a-d
^(.)(??{"(bz+|.)(.)"})(.)$ abcd y $1-$2 a-d
^(.)((??{"(.)(cz+)"})|.) abcd y $1-$2 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)(\g-2) foofoo y $1-$2 foo-foo
+(foo)(\g-2)(foo)(\g-2) foofoofoofoo y $1-$2-$3-$4 foo-foo-foo-foo
+(([abc]+) \g-1)(([abc]+) \g{-1}) abc abccba cba y $2-$4 abc-cba
+(a)(b)(c)\g1\g2\g3 abcabc y $1$2$3 abc
+
+
+/(?'n'foo) \k<n>/ ..foo foo.. y $1 foo
+/(?'n'foo) \k<n>/ ..foo foo.. y $+{n} foo
+/(?<n>foo) \k'n'/ ..foo foo.. y $1 foo
+/(?<n>foo) \k'n'/ ..foo foo.. y $+{n} foo
+/(?<as>as) (\w+) \k<as> (\w+)/ as easy as pie y $1-$2-$3 as-easy-pie