perl - split string into 2-character groups

Question

Possible Duplicate:
How can I split a string into chunks of two characters each in Perl?

I wanted to split a string into an array grouping it by 2-character pieces:

  $input = "DEADBEEF";
  @output = split(/(..)/,$input);

This approach produces every other element empty.

  $VAR1 = '';
  $VAR2 = 'DE';
  $VAR3 = '';
  $VAR4 = 'AD';
  $VAR5 = '';
  $VAR6 = 'BE';
  $VAR7 = '';
  $VAR8 = 'EF';

How to get a continuous array?

  $VAR1 = 'DE';
  $VAR2 = 'AD';
  $VAR3 = 'BE';
  $VAR4 = 'EF';

(...other than getting the first result and removing every other row...)

Thanks, Ed - probably this is the correct solution, feel free to close the question. — SF., May 19 '11 at 13:30

Tudor Constantin · Accepted Answer · 2011-05-19T13:51:04.687

3

you can easily filter out the empty entries with:

@output = grep { /.+/ } @output ;

Edit: You can obtain the same thing easier:

$input = "DEADBEEF";
my @output = ( $input =~ m/.{2}/g );

Edit 2 another version:

$input = "DEADBEEF";
my @output = unpack("(A2)*", $input);

Regards

edited May 19 '11 at 13:51

answered May 19 '11 at 13:26

Tudor Constantin

3

`a2`, not `A2`. The latter strips trailing whitespace, which is superfluous at best. – ikegami May 19 '11 at 16:30

score 2 · Answer 2 · answered May 19 '11 at 13:24

2

Try this:

$input = "DEADBEEF";
@output = ();

while ($input =~ /(.{2})/g) {
  push @output, $1;
}

answered May 19 '11 at 13:24

Doug

add the /s flag, or newlines will be skipped past (and odd characters before them) – ysth May 19 '11 at 14:21

2 Answers2