[ACCEPTED]-How can I split a string into chunks of two characters each in Perl?-split

Accepted answer
Score: 60
@array = ( $string =~ m/../g );

The pattern-matching operator behaves in 6 a special way in a list context in Perl. It 5 processes the operation iteratively, matching 4 the pattern against the remainder of the 3 text after the previous match. Then the 2 list is formed from all the text that matched 1 during each application of the pattern-matching.

Score: 43

If you really must use split, you can do a :

grep {length > 0} split(/(..)/, $string);

But 4 I think the fastest way would be with unpack :

unpack("(A2)*", $string);

Both 3 these methods have the "advantage" that 2 if the string has an odd number of characters, it 1 will output the last one on it's own.

Score: 7

Actually, to catch the odd character, you 1 want to make the second character optional:

@array = ( $string =~ m/..?/g );
Score: 6

The pattern passed to split identifies what separates that 3 which you want. If you wanted to use split, you'd 2 use something like

my @pairs = split /(?(?{ pos() % 2 })(?!))/, $string;


my @pairs = split /(?=(?:.{2})+\z)/s, $string;

Those are rather poor 1 solutions. Better solutions include:

my @pairs = $string =~ /..?/sg;  # Accepts odd-length strings.

my @pairs = $string =~ /../sg;

my @pairs = unpack '(a2)*', $string;
Score: 2

I see a more-intuitive (if perhaps less-efficient) way 5 to solve this issue: slice-off the required 4 2-character strings from the string with 3 "substr" and push them onto the 2 array with "push":

# Start with a string (a hex number in this case):
my $string = "526f62626965204861746c6579";

# Declare an array to hold the desired 2-char snippets:
my @array; 

# Snip snippets from string and put in array:
while ($string) {push @array, substr($string,0,2,"");}

# Say, those look like ASCII codes, don't they?
for (@array) {print chr(hex($_));}

Run that and 1 see what it prints. :-)

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