in reply to @ARGV in while loop

why the $ARGV[0] in while loop cannot be accessed?

Because the diamond operator (when used with the null filehandle <>) consumes the contents of @ARGV.

See the section of perlop I/O-Operators that starts with the sentence:

The null filehandle <> is special:
for the details.
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Re^2: @ARGV in while loop
by lightoverhead (Pilgrim) on Feb 14, 2014 at 17:59 UTC

    Thank you BrowserUK. You are right. It's good to learn.

    what about this:

     for(;;){
     print "3:\t$ARGV[0]\n"; #cannot print either
       last;
   }

    [download]
    Is $ARGV[0] consumed too?
[reply]
[d/l]

      my fault

      I put for(;;;) after while().

      if run for(;;) first, it will print $ARGV[0]

[reply]

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