I am currently learning Perl. I have Perl hash that contains references to hashes and arrays. The hashes and arrays may in turn contain references to other hashes/arrays.
I wrote a subroutine to parse the hash recursively and print them with proper indentation. Though the routine works as expected, my instructor was not convinced about the readability and elegance of the below code.
I would really appreciate to get the views of Perl experts here on possible optimization of the below code.
Here is my complete code snippet..
# Array of Arrays
$ref_to_AoA = [
[ "fred", "barney" ],
[ "george", "jane", "elroy" ],
[ "homer", "marge", "bart" ],
];
#Array of Hashes
$ref_to_AoH = [
{
husband => "barney",
wife => "betty",
son => "bamm bamm",
},
{
husband => "george",
wife => "jane",
son => "elroy",
},
];
# Hash of Hashes
$ref_to_HoH = {
flintstones => {
husband => "fred",
pal => "barney",
},
jetsons => {
husband => "george",
wife => "jane",
"his boy" => "elroy", # Key quotes needed.
},
simpsons => {
husband => "homer",
wife => "marge",
kid => "bart",
},
};
# Hash which contains references to arrays and hashes
$finalHash = {
'arrayofArrays' => $ref_to_AoA,
'arrayofHash' => $ref_to_AoH,
'hashofHash' => $ref_to_HoH,
};
$string = str($finalHash);
print "$string\n";
#------------------------------------------------------------------
sub str {
my $hash = shift;
my ($space, $newline, $delimiter) = @_;
$space = "" unless (defined $space);
$newline = "\n\n\n" unless (defined $newline);
$delimiter = "\n--------------------------------------------" unless (defined $delimiter);
my $str = "";
for (sort keys %{$hash}) {
my $value = $hash->{$_};
$str .= "$newline$space$_ == $value$delimiter";
$str .= recurseErrors($value,$space);
}
$str;
}
#------------------------------------------------------------------
sub recurseErrors {
my $str;
my ($value,$space) = @_;
my $ref = ref $value;
if ($ref eq 'ARRAY') {
my $i = 0;
my $isEmpty = 1;
my @array = @$value;
$space .= "\t";
for my $a (@array) {
if (defined $a) {
$isEmpty = 0;
$str .= "\n$space$_\[$i\] :";
$str .= recurseErrors($a,$space);
}
$i++;
}
$str .= "= { }" if ($isEmpty);
} elsif ($ref eq 'HASH') {
$space .= "\t";
for my $k (sort keys %$value) {
if ( ( ref($value->{$k}) eq 'HASH') || (ref $value->{$k} eq 'ARRAY') ) {
my $val = $value->{$k};
$str .= "\n\n$space$k == ";
$str .= "$val";
}
else {
$str .= "\n$space$k == ";
}
$str .= recurseErrors($value->{$k},$space);
}
# we have reached a scalar (leaf)
} elsif ($ref eq '') {
$str .= "$value";
}
$str
}
#------------------------------------------------------------------
arrayofArrays == ARRAY(0x9d9baf8) -------------------------------------------- arrayofArrays[0] : arrayofArrays[0] :fred arrayofArrays[1] :barney arrayofArrays[1] : arrayofArrays[0] :george arrayofArrays[1] :jane arrayofArrays[2] :elroy arrayofArrays[2] : arrayofArrays[0] :homer arrayofArrays[1] :marge arrayofArrays[2] :bart arrayofHash == ARRAY(0x9d9bba8) -------------------------------------------- arrayofHash[0] : husband == barney son == bamm bamm wife == betty arrayofHash[1] : husband == george son == elroy wife == jane hashofHash == HASH(0x9da45f8) -------------------------------------------- flintstones == HASH(0x9d9bb48) husband == fred pal == barney jetsons == HASH(0x9d9bbf8) his boy == elroy husband == george wife == jane simpsons == HASH(0x9d9bc48) husband == homer kid == bart wife == marge
use strict
;use warnings
as well.Apart from that I think your instructor had a bad day that day.
maybe Data::Dumper is what you want:
use Data::Dumper;
$str = Dumper($foo);
print($str);
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With