dereferencing data from multiple hash and array data structure in perl - perl

Question

Trying to extract data from detailed -> doc -> params -> parameters -> name in following DoxyDocs1.pm file; also including sample of script that extracts some data, but having trouble extracting params -> parameters -> name. Uncomment commented sections to see data.
#!/bin/perl
use Data::Dumper;
use warnings;
require "DoxyDocs1.pm";
print "API Content Analyzer\n";
&GenerateClassInfo($doxydocs->{classes});
sub GenerateClassInfo()
{
my ($classes) = #_;
foreach my $class (#$classes) {
print "\nClass name is: $class->{name}\n";
foreach my $pubmeth (#{$class->{public_methods}->{members}}) {
print "\n" if exists $pubmeth->{name};
print "\tpublic methods include: $pubmeth->{name}\n";
my ($key, $pmcontent) = each (#{$pubmeth->{detailed}->{doc}});
print "\t\tdescription: $pmcontent->{content}\n" if exists $pmcontent->{content};
# foreach my $pmp (#{$pubmeth->{detailed}->{doc}}) {
# print "\t\t";
# print Dumper($pmp);
# }
print "\t\tkind: $pubmeth->{kind}\n";
print "\t\ttype: $pubmeth->{type}\n" if exists $pubmeth->{type};
}
foreach my $privmeth (#{$class->{private_methods}->{members}}) {
print "\n" if exists $privmeth->{name};
print "\tprivate methods include: $privmeth->{name}\n";
my ($key, $pmcontent) = each (#{$privmeth->{detailed}->{doc}});
print "\t\tdescription: $pmcontent->{content}\n" if exists $pmcontent->{content};
# foreach my $info (#{$privmeth->{detailed}->{doc}}) {
# print "\t\t";
# print Dumper($info);
# }
print "\t\tkind: $privmeth->{kind}\n";
print "\t\ttype: $privmeth->{type}\n" if exists $privmeth->{type};
}
}
}
Example DoxyDocs1.pm file
$doxydocs=
{
classes => [
{
name => 'Panoply::Composite',
public_methods => {
members => [
{
kind => 'function',
name => 'addChild',
virtualness => 'non_virtual',
protection => 'public',
static => 'no',
brief => {},
detailed => {
doc => [
{
type => 'text',
content => 'Add a child to the container '
},
params => [
{
parameters => [
{
name => 'child'
}
],
doc => [
{
type => 'text',
content => 'is the child element to add'
}
]
}
]
]
},
type => 'void',
const => 'no',
volatile => 'no',
parameters => [
{
declaration_name => 'child',
type => 'Ptr'
}
]
},
{
kind => 'function',
name => 'operator<',
virtualness => 'non_virtual',
protection => 'public',
static => 'no',
brief => {},
detailed => {
doc => [
{
type => 'text',
content => 'Less than operator'
},
{
type => 'parbreak'
},
params => [
{
parameters => [
{
name => 'rval'
}
],
doc => [
{
type => 'text',
content => 'The '
},
{
type => 'url',
link => 'classPanoply_1_1Package',
content => 'Package'
},
{
type => 'text',
content => ' against which we are comparing this one. '
}
]
}
],
{
return => [
{
type => 'text',
content => 'true if this.packageID < rval.packageID, false otherwise.'
}
]
}
]
},
type => 'bool',
const => 'yes',
volatile => 'no',
parameters => [
{
declaration_name => 'rval',
type => 'const Composite &'
}
]
},
]
},
private_methods => {
members => [
{
kind => 'function',
name => 'addChild',
virtualness => 'virtual',
protection => 'private',
static => 'no',
brief => {},
detailed => {
doc => [
{
type => 'text',
content => 'Add a child to the container '
},
params => [
{
parameters => [
{
name => 'child'
}
],
doc => [
{
type => 'text',
content => 'is the child element to add '
}
]
},
{
parameters => [
{
name => 'parent'
}
],
doc => [
{
type => 'parbreak'
},
{
type => 'text',
content => 'is this own parent, except in weak pointer format to avoid a memory leak'
}
]
}
]
]
},
type => 'virtual void',
const => 'no',
volatile => 'no',
parameters => [
{
declaration_name => 'child',
type => 'Ptr'
},
{
declaration_name => 'parent',
type => 'Ptr'
}
]
},
]
},
}
]
};
1;

Answer 1

You said you wanted
detailed -> doc -> params -> parameters -> name
but that's missing many indexes. Which doc, param and parameters do you want?
detailed -> doc -> ??? -> params -> ??? -> parameters -> ??? -> name
The syntax is:
$member->{detailed}->{doc}->[$i]->{params}->[$j]->{parameters}->[$k]->{name}
Or for short:
$member->{detailed}{doc}[$i]{params}[$j]{parameters}[$k]{name}
If you want to loop over every doc, params, parameter, you can use:
my $docs = $member->{detailed}{doc};
for my $doc (#$docs) {
my $params = $doc->{params};
for my $param (#$params) {
my $parameters = $param->{parameters};
for my $parameter (#$parameters) {
...
}
}
}
(Why is doc singular and params and parameters plural??? Why do params have parameters???)