That doesn't necessarily work as intended if the values of one or more elements in either array contain the list separator $":

my @array1 = qw(one two three);
my @array2 = ("one" . $" . "two", "three");

if ("@array1" eq "@array2") {
    print 'They are the same', $/;   # no, they are NOT
}
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The updated code is still flawed, consider:

my @array1 = qw(one two three);
my @array2 = qw(onetwo three);

if ( do{ local $" = ''; "@array1" eq "@array2"} ) {
    print 'They are the same', $/;   # no, they are NOT
}
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This second update still isn't the way to do it... I took out the local $" (which should be no problem as the value of $" shouldn't matter anyway). Consider:

my @array1 = ("one", "two" . $" . "three");
my @array2 = ("one" . $" . "two", "three");

if ( do{ @array1 == @array2 and "@array1" eq "@array2"} ) { 
    print 'They are the same', $/;    # no, they are NOT
}
[download]

Stringifying would only work if it is guaranteed that $" doesn't occur as a substring of one or more values of either array.

— Arien