An enlightening ex-vivo demonstration of Perl internals: 
use strict;

my @list = 0..9;
print "Step 1: @list\n";

alias_fun(@list);
sub alias_fun {
  splice @_, 5, 5, 0..4;
  $_ = 'X' for @_;
  print "Step 2: @_\n";
}

print "Step 3: @list\n";

[download]
Mondo ++ to whomever can guess the SoPW question that inspired the pathological code above.

In reply to Aliases upon aliases by Pragma

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