Issue in Printing data from a hash table in perl - perl

Question

I am trying to process the data in a single file . i have to read the file and create a hash structure,get the value of fruitname append it to fruitCount and fruitValue and delete the line fruitName and write the entire output after the change is done.Given below is the content of file.
# this is a new file
{
date 14/07/2016
time 11:15
end 11:20
total 30
No "FRUITS"
Fruit_class
{
Name "fruit 1"
fruitName "apple.fru"
fruitId "0"
fruitCount 5
fruitValue 6
}
{
Name "fruit 2"
fruitName "orange.fru"
fruitId "1"
fruitCount 10
fruitValue 20
}
}
I tried with following code :
#!/usr/bin/perl
use strict;
use warnings;
use Data::Dumper;
my %hash_table;
my $name;
my $file = '/tmp/fruitdir/fruit1.txt';
open my $fh, "<", $file or die "Can't open $file: $!";
while (<$fh>) {
chomp;
if (/^\s*fruitName/) {
($name) = /(\".+\")/;
next;
}
s/(fruitCount|fruitValue)/$name\.$1/;
my ($key, $value) = split /\s+/, $_, 2;
$hash_table{$key} = $value;
}
print Dumper(\%hash_table);
This is not working . I need to append the value of fruitname and print the the entire file content as output. Any help will be appreciated.Given below is the output that i got.
$VAR1 = {
'' => undef,
'time' => '11:15 ',
'date' => '14/07/2016',
'{' => undef,
'#' => 'this is a new file',
'total' => '30 ',
'end' => '11:20 ',
'No' => '"FRUITS"',
'Fruit_class' => undef,
'}' => undef
};
Expected hash as output:
$VAR1 = {
'Name' => '"fruit 1"',
'fruitId' => '"0" ',
'"apple_fru".fruitValue' => '6 ',
'"apple_fru".fruitCount' => '5'
'Name' => '"fruit 2"',
'fruitId' => '"0" ',
'"orange_fru".fruitValue' => '10 ',
'"orange_fru".fruitCount' => '20'
};

Answer 1

One word of advice before I continue:
Document your code
There are several logic errors in your code which I think you would have recognized if you wrote down what you thought each line was supposed to do. First, write down the algorithm that you would like to implement, then document how each step in the code implements a step in the algorithm. At the end you'll be able to see what you missed, or what part is not working.
Here are the errors that I see
You aren't ignoring lines that you shouldn't be parsing. For example, you're grabbing the '}' and '{' lines.
You aren't actually storing the name of the fruit. You grab it, but immediately start the next loop without storing it.
You're not keeping track of each structure. You need to start a new structure for each fruit.
Do you really want to keep the double quotes in the values?
Other things to worry about:
Are you guaranteed that the list of attributes is in that order? For example, can Name come last?
Here's some code which does what I think you want.
#!/usr/bin/perl
use strict;
use warnings;
use Data::Dumper;
my %hash_table;
my $name;
my #fruit;
my $file = '/tmp/fruitdir/fruit1.txt';
open my $fh, "<", $file or die "Can't open $file: $!";
while (<$fh>) {
chomp;
# save hash table if there's a close bracket, but
# only if it has been filled
if ( /^\s*}\s*$/ ) {
next unless keys %hash_table;
# save COPY of hash table
push #fruit, { %hash_table };
# clear it out for the next iteration
%hash_table = ();
}
# only parse lines that start with Name or fruit
next unless
my ( $key, $value ) =
/^
# skip any leading spaces
\s*
# parse a line beginning with Name or fruitXXXXX
(
Name
|
fruit[^\s]+
)
# need space between key and value
\s+
# everything that follows is a value. clean up
# double quotes in post processing
(.*)
/x;
# remove double quotes
$value =~ s/"//g;
if ( $key eq 'Name' ) {
$name = $value;
}
else {
$key = "${name}.${key}";
}
$hash_table{$key} = $value;
}
print Dumper \#fruit;
and here's the output:
$VAR1 = [
{
'fruit 1.fruitValue' => '6',
'fruit 1.fruitName' => 'apple.fru',
'Name' => 'fruit 1',
'fruit 1.fruitCount' => '5',
'fruit 1.fruitId' => '0'
},
{
'fruit 2.fruitName' => 'orange.fru',
'fruit 2.fruitId' => '1',
'fruit 2.fruitCount' => '10',
'fruit 2.fruitValue' => '20',
'Name' => 'fruit 2'
}
];