There wasn't much input you supplied, so I made assumptions that all numbers will be in either one or two of those formats. I'll leave it up to you to hack as necessary to handle other formats (I left the else-if open). Also, I'll leave the exercise of changing the input file from __DATA__ to an actual file, but the open for writing line should help

#!/usr/bin/perl

use warnings;
use strict;

open my $fh, '+>', 'output.txt'
  or die("Can't open the damn file!: $!");

while(my $line = <DATA>){
    chomp $line;
    my ($name, $num) = split(/\s+(?=\d)/, $line);

    # some lines have whitespace after the num

    $num =~ s/\s+//g;

    if ($num =~ /^\d{4}$/){
        $num = "(333)-321-$num";
    }
    elsif ($num =~ /^\d{3}-\d{4}$/){
        $num = "(333)-$num";
    }

    print $fh "$name $num\n";
}

__DATA__
Black, Joe 0987
Smith, Sue 0534
Brown, Andy 587-0986

[download]

Output:

$ cat output.txt 
Black, Joe (333)-321-0987
Smith, Sue (333)-321-0534
Brown, Andy (333)-587-0986

[download]

-stevieb

In reply to Re: total noob trying to format a phone list by stevieb
in thread trying to format a list by sonikd

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