Finally, Match does Positional.

src/core/Match.pm

@@ -1,4 +1,4 @@
-class Match is Regex::Match is Cool does Associative {
+class Match is Regex::Match is Cool does Positional does Associative {
     method ast() {
         my $x = self.Regex::Match::ast;
         pir::isa__IPs($x, 'Undef') ?? Any !! $x;
@@ -8,7 +8,8 @@ class Match is Regex::Match is Cool does Associative {
         ~self.Regex::Match::Str;
     }
 
-    multi method postcircumfix:<{ }>($key) {
+
+    method at_key($key) {
         Q:PIR {
             $P0 = find_lex 'self'
             $P1 = find_lex '$key'
@@ -21,17 +22,10 @@ class Match is Regex::Match is Cool does Associative {
         }
     }
 
-    # We shouldn't need to provide this -- we should be able to
-    # simply write "does Positional" in the class declaration
-    # and it would provide us the postcircumfix:<[ ]> methods
-    # for free.  But there seems to be a bug or problem in the
-    # role composer that prevents us from having both "does Positional"
-    # and "does Associative" in the class declaration, so we'll
-    # provide the simple .[] for now.
-    multi method postcircumfix:<[ ]>(Int $key) {
+    method at_pos($pos) {
         Q:PIR {
             $P0 = find_lex 'self'
-            $P1 = find_lex '$key'
+            $P1 = find_lex '$pos'
             $I1 = $P1
             %r = $P0[$I1]
             unless null %r goto done
@@ -42,6 +36,8 @@ class Match is Regex::Match is Cool does Associative {
         }
     }
 
+    method of() { Mu }
+
     multi method hash() {
         # nextsame() dies here with 'Null PMC access in clone()'
         CREATE_HASH_FROM_LOW_LEVEL(self.Regex::Match::hash);