Huh? 
$ perl -wE '$f = "foo"; say pos $f while $f =~ m{ ( o? )* }gx;'
0
3
3

[download]

map{substr$_->[0],$_->[1]||0,1}[\*||{},3],[[]],[ref qr-1,-,-1],[{}],[sub{}^*ARGV,3]

In reply to Re^3: Is it safe to use external strings for regexes? (infinite loops) by choroba
in thread Is it safe to use external strings for regexes? by stevieb

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