[perl #130354] last without doesn't

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# New Ticket Created by  Elizabeth Mattijsen 
# Please include the string:  [perl #130354]
# in the subject line of all future correspondence about this issue. 
# <URL: https://rt.perl.org/Ticket/Display.html?id=130354 >


lizmat  m: loop { last without index("a","foo") }   # feels to me this 
shouldn't hang ?
camelia rakudo-moar b28604: OUTPUT«(timeout)»
m: loop { print "foo" without index("a","foo") }   # feels to me this shouldn't 
hang ?
camelia rakudo-moar b28604: 
OUTPUT«(timeout)foofoofoofoofoofoofoofoofoofo​ofoofoofoofoofoofoofoofoofoofoofoofoofoofoofo​ofoofoofoofoofoofoofoofoofoofoofoofoofoofoofo​ofoofoofoofoofoofoofoofoofoofoofoofoofoofoofo​ofoofoofoofoofoofoofoofoofoofoofoofoofoofoofo​ofoofoofoofoofoofoofoofoofoofoofoofoof…»
jnthn   m: say index("a","foo")
camelia rakudo-moar b28604: OUTPUT«Nil␤»
jnthn   m: say index("a","foo").defined
camelia rakudo-moar b28604: OUTPUT«False␤»
jnthn   m: say index("a","foo").DEFINITE
camelia rakudo-moar b28604: OUTPUT«False␤»
jnthn   Yeah, looks busted and I'm not sure why :)
lizmat  m: say ?index("a","foo")
camelia rakudo-moar b28604: OUTPUT«False␤»
jnthn   without should care about .defined fwiw
lizmat  m: loop { last not with index("a","foo") }   # also odd?
camelia rakudo-moar b28604: OUTPUT«===SORRY!=== Error while compiling 
<tmp>␤Undeclared routine:␤    with used at line 1␤␤»
lizmat  m: FOO: loop { last FOO without index("a","foo") }   # this works
camelia rakudo-moar b28604: ( no output )