Dear Monks:

I found an interesting case of regex. This is actually from Programing Perl 4th errata.

The output of the following line of code is different than what is des
+cribed in the text:
"abcdef" =~ / .+ (?{say "Matched so far: $&"}) bcdef $/x;

The text states that this prints the following:

Matched so far: abcdef
Matched so far: abcde
Matched so far: abcd
Matched so far: abc
Matched so far: ab
Matched so far: a

But I am finding that only the last line gets printed:

Matched so far: a

One solution to get the output that the text describes is to slightly 
+modify the code example to the following:

"abcdef" =~ / .+ (?{say "Matched so far: $&"}) .cdef $/x;
[download]

I am wondering why "backtrack" doesn't behave the way originally expected and why the edited version works?

Thank you!

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