When you loop over your array $_ becomes an alias for each item so you are in fact modifying the array.
From perlfaq4

     How do I process/modify each element of an array?

     Use for/foreach:

         for (@lines) {
             s/foo/bar/;     # change that word
             y/XZ/ZX/;       # swap those letters
         }

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And now, as he looked and saw the whole Hellespont covered with the vessels of his fleet, and all the shore and every plain about Abydos as full as possible of men, Xerxes congratulated himself on his good fortune; but after a little while he wept...
Asked why he was weeping he replied
..."There came upon me," replied he, "a sudden pity, when I thought of the shortness of man's life, and considered that of all this host, so numerous as it is, not one will be alive when a hundred years are gone by."
Recorded by Herodotus Written about 440 B.C.

In reply to Re: What Is Going On Here ????? by Jonathan
in thread What Is Going On Here ????? by orthanc

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