Question

Code:

$_ = "Sample sentence with 00-B0-D0-86-BB-F7 MAC address in the middle";
my ($a, $mac, $b) = 
  split('/([0-9A-F]{2}[:-]){5}([0-9A-F]{2})/', $_);
print $mac;
print "\n";

For some reason $mac is always empty, and I don’t know why.

Answer 1

If you supply split with a string as the first argument it will split on that string as if it were a regex.

split ':', $str;

Is really a DWIM of:

split /:/, $str;

---

So your code of:

split('/([0-9A-F]{2}[:-]){5}([0-9A-F]{2})/', $_);

Really means

split(m[/([0-9A-F]{2}[:-]){5}([0-9A-F]{2})/], $_);
# or
split(/\/([0-9A-F]{2}[:-]){5}([0-9A-F]{2})\//, $_);

---

Also you want split to save the value that it matches on, so you want the whole match to be in ().

$_ = "Sample sentence with 00-B0-D0-86-BB-F7 MAC address in the middle";
my ($a, $mac, $b) = split(/((?:[0-9A-F]{2}[:-]){5}[0-9A-F]{2})/, $_);
print $mac, "\n";

---

Since you appear to only use $mac you don’t have to use split.

my ($mac) = /((?:[0-9A-F]{2}[:-]){5}[0-9A-F]{2})/;
# or
my @macs = /((?:[0-9A-F]{2}[:-]){5}[0-9A-F]{2})/g;