SNMP::Info::MRO(3) Method resolution introspection for SNMP::Info

SYNOPSIS


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

p SNMP::Info::MRO::all_methods('SNMP::Info::Layer3::Juniper');

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 <[email protected]>

COPYRIGHT AND LICENSE

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

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