# New Ticket Created by Aaron Sherman
# Please include the string: [perl #69552]
# in the subject line of all future correspondence about this issue.
# <URL: http://rt.perl.org/rt3/Ticket/Display.html?id=69552 >
When .subst has a void or Bool context, it should issue a warning, since
there is no logical reason to perform such an action (in a Bool context,
it's just being used to perform a match, for which a match should be used,
not a substitution).
This will avoid the confusion embodied in this test program:
my $s = "abc";
while $s.subst(regex { <+lower> }, '') {
print ~$/
}
which one might expect to print "abc", but instead prints an infinite
sequence of "aaaa..." becuase it performs substitution on a copy, not
in-place.
