NAME

SNMP::Info::MRO - Method resolution introspection for SNMP::Info

SYNOPSIS

use SNMP::Info::MRO;
use Data::Printer;

# SNMP::Info::MRO::print_* functions
SNMP::Info::MRO::print_superclasses ('SNMP::Info::Layer3::Juniper');

# print output using Data::Printer for other functions
my $buff = SNMP::Info::MRO::all_methods('SNMP::Info::Layer3::Juniper');
p $buff;

DESCRIPTION

This is a set of helpers to show where a given method in SNMP::Info has been implemented, and which implementation is being used at runtime.

The following distributions are required to run this code:

• PPI

• Class::ISA

• Module::Info

• Module::Load

FUNCTIONS

None of the functions are exported. For all helper functions, you can pass either the name of a Perl module, or an object instance of SNMP::Info.

all_methods( $module )

Returns the location of methods defined in $module and all its ancestor classes (superclasses), either as Perl subroutines or via %GLOBALS or %FUNCS configuration. The data structure looks like:

{
  method_name => {
    globals => [
      [ Package::Name        => 'mib_leaf.0' ],
      [ Other::Package::Name => '1.3.6.1.4.1.9.2.1.58.0' ],
    ],
  },
  other_method_name => [
    subs => [
      'Package::Name',
    ],
    funcs => [
      [ Package::Name => 'mib_leaf_name' ],
    ],
  ],
}

It should be noted that the order of method resolution in SNMP::Info is to first look for a defined subroutine (this is done by Perl), then the AUTOLOAD sequence will search for a definition in %GLOBALS followed by %FUNCS.

The defining class or module at runtime is always the first entry in the list, if it exists:

$data->{method_name}->{subs}->[0]
  if exists $data->{method_name}->{subs};

subroutines( $module )

Returns the set of subroutines defined in $module and all its ancestor classes (superclasses). The data structure looks like:

{
  method_name => [
    'Package::Name',
    'Other::Package::Name',
  ],
  other_method_name => [
    'Package::Name',
  ],
}

Should a subroutine have been defined more than once, the defining classes are listed in reverse order, such that the definition used at runtime is always:

$data->{method_name}->[0];

globals( $module || $object )

Returns a data structure showing how SNMP::Info will resolve MIB Leaf Nodes configured through the %GLOBALS hashes in $module.

The data structure looks like:

{
  method_name => [
    [ Package::Name        => 'mib_leaf_name' ],
    [ Other::Package::Name => '1.3.6.1.4.1.9.2.1.58.0' ],
  ],
  other_method_name => [
    [ Package::Name => 'mib_leaf.0' ],
  ],
}

Where a method has been defined in different packages, then they are listed in reverse order, such that the mapping used by SNMP::Info is always:

$data->{method_name}->[0];

funcs( $module || $object )

Returns a data structure showing how SNMP::Info will resolve MIB Tables configured through the %FUNCS hashes in $module.

See "GLOBALS" in SNMP::Info::Layer3 for further detail.

munge( $module || $object )

Returns a data structure showing the subroutines used for munging returned values for any method defined in %FUNCS or %GLOBALS.

The data structure looks like:

{
  method_name => [
    [ Package::Name        => '&subroutine' ],
    [ Other::Package::Name => '&Other::Package::subroutine' ],
  ],
  other_method_name => [
    [ Package::Name => '&subroutine' ],
  ],
}

Where a mapping has been defined in different packages, then they are listed in reverse order, such that the munge subroutine used by SNMP::Info is always:

$data->{method_name}->[0];

file( $module )

Returns the filename from which Perl will load the given module.

superclasses( $class || $object )

Returns the list (in order) of the names of classes Perl will search to find methods for this SNMP::Info class or object instance.

Note this requires the Class:ISA distribution to be installed.

print_globals( $module || $object )

Pretty print the output of globals().

print_funcs( $module || $object )

Pretty print the output of funcs().

print_munge( $module || $object )

Pretty print the output of munge().

print_superclasses( $class || $object )

Pretty print the output of superclasses().

AUTHOR

Oliver Gorwits <oliver@cpan.org>

COPYRIGHT AND LICENSE

This software is copyright (c) 2014 by The SNMP::Info Project.

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