User::Identity::Archive::Plain(3)

NAME
User::Identity::Archive::Plain - simple, plain text archiver

INHERITANCE
 User::Identity::Archive::Plain
   is a User::Identity::Archive
   is a User::Identity::Item

SYNOPSIS
  use User::Identity::Archive::Plain;
  my $friends = User::Identity::Archive::Plain->new('friends');
  $friends->from(\*FH);
  $friends->from('.friends');

DESCRIPTION
This archiver, which extends User::Identity::Archive, uses a very simple plain text file to store the information of users. The syntax is described in the DETAILS section, below.

Extends "DESCRIPTION" in User::Identity::Archive.

OVERLOADED
Extends "OVERLOADED" in User::Identity::Archive.

METHODS
Extends "METHODS" in User::Identity::Archive.

  Constructors
Extends "Constructors" in User::Identity::Archive.

$class->new( [$name], %options )

     -Option       --Defined in             --Default
      abbreviations                           []
      description    User::Identity::Item     undef
      from           User::Identity::Archive  undef
      name           User::Identity::Item     <required>
      only                                    []
      parent         User::Identity::Item     undef
      tabstop                                 8

    abbreviations => HASH|ARRAY
        Adds a set of abbreviations for collections to the syntax of the plain text archiver. See section "Simplified class names" for a list of predefined names.

    description => STRING
    from => $filehandle|$file
    name => STRING
    only => \@abbrevs|$abbrev
        Lists the only information (as (LIST of) abbreviations) which should be read. Other information is removed before even checking whether it is a valid abbreviation or not.

    parent => OBJECT
    tabstop => INTEGER
        Sets the default tab-stop width.

  Attributes
Extends "Attributes" in User::Identity::Archive.

$obj->abbreviation( $name, [$class] )
    Returns the class which is capable of storing information which is grouped as $name. With $class argument, you add (or overrule) the definitions of an abbreviation. The $class is automatically loaded.

    If $class is "undef", then the abbreviation is deleted. The class name which is deleted is returned.

$obj->abbreviations()
    Returns a sorted list of all names which are known as abbreviations.

$obj->defaultTabStop( [$integer] )
    Returns the width of a tab, optionally after setting it. This must be the same as set in your editor.

$obj->description()
    Inherited, see "Attributes" in User::Identity::Item

$obj->name( [$newname] )
    Inherited, see "Attributes" in User::Identity::Item

  Collections
Extends "Collections" in User::Identity::Archive.

$obj->add($collection, $role)
    Inherited, see "Collections" in User::Identity::Item

$obj->addCollection( $object | <[$type], %options> )
    Inherited, see "Collections" in User::Identity::Item

$obj->collection($name)
    Inherited, see "Collections" in User::Identity::Item

$obj->parent( [$parent] )
    Inherited, see "Collections" in User::Identity::Item

$obj->removeCollection($object|$name)
    Inherited, see "Collections" in User::Identity::Item

$any->type()
    Inherited, see "Collections" in User::Identity::Item

$obj->user()
    Inherited, see "Collections" in User::Identity::Item

  Searching
Extends "Searching" in User::Identity::Archive.

$obj->find($collection, $role)
    Inherited, see "Searching" in User::Identity::Item

  Access to the archive
Extends "Access to the archive" in User::Identity::Archive.

$obj->from( <$fh|$filename|ARRAY>, %options )
    Read the plain text information from the specified $fh, $filename, STRING, or "ARRAY" of lines. Improves base, see "Access to the archive" in User::Identity::Archive

     -Option --Default
      tabstop  <default from object>

    tabstop => INTEGER

DETAILS

  The Plain Archiver Format
Simplified class names

It is too much work to specify full class named on each spot where you want to create a new object with data. Therefore, abbreviations are introduced. Use new(abbreviations) or abbreviations() to add extra abbreviations or to overrule some predefined.

Predefined names:
  user User::Identity
  email Mail::Identity
  location User::Identity::Location
  system User::Identity::System
  list User::Identity::Collection::Emails

It would have been nicer to refer to a person in stead of a user, however that would add to the confusion with the name-space.

Indentation says all

The syntax is as simple as possible. An extra indentation on a line means that the variable or class is a collection within the class on the line before.

  user markov
    location home
       country NL
    email home
       address  mark@overmeer.net
       location home
    email work
       address  solutions@overmeer.bet

  email tux
     address tux@fish.net

The above defines two items: one User::Identity named "markov", and an e-mail address "tux". The user has two collections: one contains a single location, and one stores two e-mail addresses.

To add to the confusion: the "location" is defined as field in "email" and as collection. The difference is easily detected: if there are indented fields following the line it is a collection. Mistakes will in most cases result in an error message.

Long lines

If you want to continue on the next line, because your content is too large, then add a backslash to the end, like this:

  email home
     description This is my home address,     \
                 But I sometimes use this for \
                 work as well
     address tux@fish.aq

Continuations do not play the game of indentation, so what you also can do is:

  email home
     description               \
  This is my home address,     \
  But I sometimes use this for \
  work as well
     address tux@fish.aq

The fields "comment" and "address" must be correctly indented. The line terminations are lost, which is useful for most fields. However, if you need them, you have to check the description of the applicable field.

Comments

You may add comments and white spaces. Comments start with a '#' as first non-blank character on the line. Comments are not allowed on the same line as real data, as some languages (like Perl) permit.

You can insert comments and blank lines on all places where you need them:

  user markov

     # my home address
     email home

        # useless comment statement
        address tux@fish.aq
        location #mind_the_hash

is equivalent to:

  user markov
     email home
        address tux@fish.aq
        location #mind_the_hash

References

Often you will have the need to add the same information to two items, for instance, multiple people share the same address. In this case, you can create a reference. However, this is only permitted for whole items: you can refer to someone's location, but not to the person's street.

To create a reference to an item of someone else, use

  user markov
     location home = user(cleo).location(home)
     location work
        organization   MARKOV Solutions

Configuration parameters

You can add some configuration lines as well. On the moment, the only one defined is

  tabstop = 4

which can be used to change the meaning of tabs in the file. The default setting is 8, but some people prefer 4 (or other values).

DIAGNOSTICS

Error: cannot load collection module for $type ($class): $@
    Either the specified $type does not exist, or that module named $class returns compilation errors. If the type as specified in the warning is not the name of a package, you specified a nickname which was not defined. Maybe you forgot the 'require' the package which defines the nickname. Cast by addCollection()

Error: cannot read archive from a $type.
    Cast by from()

Fault: cannot read archive from file $file: $!
    Cast by from()

Error: nvalid collection $name.
    The collection with $name does not exist and can not be created. Cast by add()

Warning: option 'only' specifies undefined abbreviation '$abbrev'.
    Cast by new()

Info: reading archive data from $source.
    Cast by from()

Error: this $object is not a collection.
    Cast by addCollection()

SEE ALSO
This module is part of User-Identity version 4.00, built on December 12, 2025. Website: http://perl.overmeer.net/CPAN/

LICENSE
For contributors see file ChangeLog.

This software is copyright (c) 2003-2025 by Mark Overmeer.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.