Perl: Copying array elements into single string

Question

I am trying to copy each array elements with slight modification into single string variable in Perl. What I want is to copy each element by adding 0x prefix into string. This is what I have tried so far:

#!usr/bin/perl

  use strict;
  use warnings;

  my @values = (01, 02, 03, 04);
  my $res = "";
  
  foreach my $val (@values) {
    $res = join '', "0x", "$val", ", ";
  }

  print "$res\n";
 
  exit 0;

As a result I got just 0x04,. Wanted result should be like: 0x01, 0x02, 0x03, 0x04

sticky bit · Accepted Answer · 2020-07-31 13:08:16Z

3

In your loop you overwrite the string in every iteration. That is why you only get the last value.

You can use join() over the whole array, not just the individual parts of an element. To prefix and zero pad the numbers and get their hexadecimal representation in the array you can use map() and sprintf().

#!/usr/bin/perl

use strict;
use warnings;

my @values = (01, 02, 03, 04);
my $res = '';

$res = join(', ', map({ sprintf('0x%02x', $_) } @values));

print("$res\n");

exit(0);

(Also note, that your shebang was missing the leading forward slash (/). Most likely that's not intentional.)

edited Jul 31, 2020 at 13:08

answered Jul 31, 2020 at 10:28

sticky bit

37.7k12 gold badges34 silver badges46 bronze badges

Sign up to request clarification or add additional context in comments.

3 Comments

Emiliano Over a year ago

I totally understood your code. Just one minor note: Since hex values are not only consisting of numerical values better to use %s instead of %i

ikegami Over a year ago

The OP probably wants the hex representation of the numbers. For that, use sprintf('0x%02x', $_)

sticky bit Over a year ago

@Emil: If there are numbers in the array and you want the hexadecimal representation of them (which I probably should have guessed by the 0x prefix), you can use x instead of i in sprintf(). I edited the answer.

vkk05 · Accepted Answer · 2020-07-31 10:26:18Z

0

Try in this way:

#!/usr/bin/perl

use strict;
use warnings;

use Data::Dumper;

my @values = (01, 02, 03, 04);
my @array;

foreach my $val (@values) {
    push (@array, "0x".$val);
}

print Dumper(\@array);

my $res = join(",", @array);
print $res;

answered Jul 31, 2020 at 10:26

vkk05

3,23215 silver badges41 bronze badges

1 Comment

ikegami Over a year ago

The OP probably wants the hex representation of the numbers. For that, use sprintf('0x%02x', $val)

Collectives™ on Stack Overflow

Perl: Copying array elements into single string

2 Answers 2

3 Comments

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

3 Comments

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related