add method Label.gist, .redo and .next

Label.gist looks like this (with colors):
perl6-m -e 'my $x; my $y; BAR: while $x++ < 2 { }; say BAR'
Label<BAR>(at -e:1, 'my $x; my $y; ⏏BAR:while $x++ < 2 { };')

src/Perl6/Grammar.nqp

@@ -1105,7 +1105,7 @@ grammar Perl6::Grammar is HLL::Grammar does STD {
         <identifier> ':' <?[\s]> <.ws>
         {
             $*LABEL := ~$<identifier>;
-            my $label := $*W.find_symbol(['Label']).new($*LABEL);
+            my $label := $*W.find_symbol(['Label']).new( :name($*LABEL), :match($/) );
             $*W.add_object($label);
             $*W.install_lexical_symbol($*W.cur_lexpad(), $*LABEL, $label);
         }

src/core/PseudoStash.pm

@@ -3,21 +3,53 @@ my class X::Caller::NotDynamic { ... }
 
 my class Label {
     has Str $!name;
-    method new($name) {
+    has Mu $!match;
+    method new(:$name, Mu :$match) {
         # XXX register in &?BLOCK.labels
         my $obj := nqp::create(self);
-        nqp::bindattr($obj, Label, '$!name', $name);
+        nqp::bindattr($obj, Label, '$!name',  $name);
+        nqp::bindattr($obj, Label, '$!match', $match);
         $obj
     }
     method name() {
         $!name
     }
+    method match() {
+        $!match
+    }
     # XXX method leave(@args)
     # XXX method goto
-    # XXX method next
+    method gist() {
+        my $file  = nqp::getlexdyn('$?FILES');
+        $file     = nqp::box_s((nqp::isnull($file) ?? '<unknown file>' !! $file), Str);
+        my $line  = HLL::Compiler.lineof($!match.orig, $!match.from);
+        my $left  = nqp::substr($!match.orig, 0, $!match.from);
+        my $right = nqp::substr($!match.orig, $!match.to, $!match.orig.chars - $!match.to);
+        $left     = $left.match(/   \N ** 0..20 $/).Str.trim-leading;
+        $right    = $right.match(/^ \N ** 0..20  /).Str.trim-trailing;
+
+        my $color = %*ENV<RAKUDO_ERROR_COLOR> // $*OS ne 'MSWin32';
+        my ($red, $green, $yellow, $clear) = $color
+            ?? ("\e[31m", "\e[32m", "\e[33m", "\e[0m")
+            !! ("", "", "", "");
+        my $eject = $*OS eq 'MSWin32' ?? "<HERE>" !! "\x[23CF]";
+
+        "Label<$!name>(at $file:$line, '$green$left$yellow$eject$red$!name:$green$right$clear')"
+    }
+    method next() {
+        my Mu $ex := nqp::newexception();
+        nqp::setpayload($ex, self);
+        nqp::setextype($ex, nqp::const::CONTROL_NEXT + nqp::const::CONTROL_LABELED);
+        nqp::throw($ex);
+    }
+    method redo() {
+        my Mu $ex := nqp::newexception();
+        nqp::setpayload($ex, self);
+        nqp::setextype($ex, nqp::const::CONTROL_REDO + nqp::const::CONTROL_LABELED);
+        nqp::throw($ex);
+    }
     method last() {
-        say $!name ~ '.last called';
-        my Mu $ex   := nqp::newexception();
+        my Mu $ex := nqp::newexception();
         nqp::setpayload($ex, self);
         nqp::setextype($ex, nqp::const::CONTROL_LAST + nqp::const::CONTROL_LABELED);
         nqp::throw($ex);