Validate IP address

[rvBasic]

A search on the fora returned me amongst other this sub:

sub is_ipv4 {
    my $self = shift if ref($_[0]); 
    my $value = shift;
 
    return unless defined($value);
 
    my(@octets) = $value =~ /^(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})$/;
    return unless (@octets == 4);
    foreach (@octets) {
        return unless ($_ >= 0 && $_ <= 255);
    }
 
    return join('.', @octets);
}

Can somebody explain what the first statement is used for? I see no further use of $self in this sub?


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In theory, there is no difference between theory and practice. In practice, there is. [attributed to Yogi Berra]

 

[yai]

I don't know the context from which you took this sub. I suppose it can be used with a object reference as first paramter and a value as the second OR with only a value. In the first case, the object reference is simply ignored.
HTH,
yai