As other people have mentioned, what you're copying are references (as indicated by the de-referencing arrows that you're using in the greps). Namely, your array @temp_open_single is, presumably, an array of arrayrefs.

Let's say that the first arrayref is pointing to the array at 0x18045c0, and that that array passes the test in the grep for @unique_terminal_id. Then @unique_terminal_id also contains a reference to the array at 0x18045c0. Let's suppose further that that array also passes the test in the grep for @unique_manufacturer_model. Then @unique_manufacturer_model also contains a reference to the—exact same!—array at 0x18045c0. It is copying the reference, not the referent.

That means that, when you refer to $unique_terminal_id[0][0] or to $unique_manufacturer_model[0][0], in either case you're just looking at the entry at index 0 of the single array at 0x18045c0. After you change that single array in one place, the changes will still be visible even if you look at it from another location. As others have mentioned, you need something like Storable's dclone function (which makes a 'deep clone') will allow you to avoid this difficulty.

In reply to Re^3: Updating 1 array affects the other array by JadeNB
in thread Updating 1 array affects the other array by iphony

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.