From 0a0508d6a59ddb631300cd8e9d10206f6d0bf6e2 Mon Sep 17 00:00:00 2001
From: Timo Paulssen <timonator@perpetuum-immobile.de>
Date: Fri, 20 Jan 2017 12:37:44 +0100
Subject: [PATCH] allow whenever blocks to use `redo`

---
 src/core/Supply.pm | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/src/core/Supply.pm b/src/core/Supply.pm
index 424ffe893db..e4245e6ecc1 100644
--- a/src/core/Supply.pm
+++ b/src/core/Supply.pm
@@ -1683,9 +1683,20 @@ sub SUPPLY(&block) {
             $state.run-operation({
                 my &*ADD-WHENEVER = sub ($supply, &whenever-block) {
                     $state.increment-active();
+                    my $redoable = -> \value {
+                        loop {
+                            nqp::handle(
+                                nqp::stmts(whenever-block(value), last),
+                                'REDO', 0)
+                        }
+                    }
                     my $tap = $supply.tap(
                         -> \value {
-                            self!run-supply-code({ whenever-block(value) }, $state)
+                            self!run-supply-code({
+                                nqp::handle(
+                                    whenever-block(value),
+                                    'REDO', $redoable(value))
+                            }, $state)
                         },
                         done => {
                             $state.delete-active-tap($tap) if $tap.DEFINITE;