Mail::...:Subset(3pm)

📦
version 4.02 · 9 versions
, in ubuntu stonking

💖 Mail::...:Subset(3pm) — user contributed perl documentation ✨

okay bestie, buckle up 🎀 this is Mail::Message::Head::Subset, straight out of the User Contributed Perl Documentation collection, running on perl v5.40.1. she's a little subset of header info and she is, quite frankly, iconic 💅

💜 NAME

Mail::Message::Head::Subset — subset of header information of a message 🦋

🌸 INHERITANCE

she's got main character energy and a whole family tree, look:

Mail::Message::Head::Subset realizes a Mail::Message::Head::Complete

Mail::Message::Head::Subset
  is a Mail::Message::Head
  is a Mail::Reporter

so Mail::Message::Head::Subset realizes a Mail::Message::Head::Complete, is a Mail::Message::Head, and is a Mail::Reporter. it's giving legacy dynasty 👑

✨ SYNOPSIS

my $subset = Mail::Message::Head::Subset->new(...)
$subset->isa('Mail::Message::Head')  # true
$subset->guessBodySize               # integer or undef
$subset->isDelayed                   # true

look at her go 😭 isa('Mail::Message::Head') is true, guessBodySize hands you an integer or undef, and isDelayed is true. no cap.

🦋 DESCRIPTION

so here's the tea ☕ some types of folders contain an index file which lists a few lines of information per messages. especially when it is costly to read header lines, the index speeds-up access considerably. for instance, the subjects of all messages are often wanted, but waiting for a thousand messages of the folder to be read may imply a thousand network reads (IMAP) or file openings (MH) 💀

like literally, a thousand. imagine.

when you access header fields which are not in the header subset, the whole header has to be parsed (which may consume considerable time, depending on the type of folder). so the vibe check is: if it's in the subset, slay, instant. if it's not, bestie, we're loading the whole thing 🫶

Extends "DESCRIPTION" in Mail::Message::Head.

🌈 OVERLOADED

Extends "OVERLOADED" in Mail::Message::Head.

  • overload: "" stringifaction — Inherited, see "OVERLOADED" in Mail::Message::Head
  • overload: bool true/false — Inherited, see "OVERLOADED" in Mail::Message::Head

(yes the original says "stringifaction", we don't fix it, we respect it 💖)

💅 METHODS

Extends "METHODS" in Mail::Message::Head.

🎀 Constructors

Extends "Constructors" in Mail::Message::Head.

  • $class->build( [PAIR|$field]-LIST ) — Inherited, see "Constructors" in Mail::Message::Head
  • $class->new(%options) — Inherited, see "Constructors" in Mail::Message::Head

🍓 Attributes

Extends "Attributes" in Mail::Message::Head.

(no extra entries here babes, just the inherited ones from up the tree — she said what she said 💅)

👑 The header

Extends "The header" in Mail::Message::Head.

  • $obj->isDelayed() — Inherited, see "The header" in Mail::Message::Head
  • $obj->isEmpty() — Inherited, see "The header" in Mail::Message::Head
  • $obj->isModified() — Inherited, see "The header" in Mail::Message::Head
  • $obj->knownNames() — Inherited, see "The header" in Mail::Message::Head
  • $obj->message( [$message] ) — Inherited, see "The header" in Mail::Message::Head
  • $obj->modified( [BOOLEAN] ) — Inherited, see "The header" in Mail::Message::Head
  • $obj->orderedFields() — Inherited, see "The header" in Mail::Message::Head

🔥 Access to the header

Extends "Access to the header" in Mail::Message::Head.

  • $obj->count($name) — count the number of fields with this $name. if the $name cannot be found, the full header get loaded. in case we find any $name field, it is decided we know all of them, and loading is not needed. like, one sighting of $name and she trusts the whole squad 💖
  • $obj->get( $name, [$index] ) — get the data which is related to the field with the $name. the case of the characters in $name does not matter. when a $name is used which is not known yet, realization will take place. Improves base, see "Access to the header" in Mail::Message::Head
  • $obj->study( $name, [$index] ) — Inherited, see "Access to the header" in Mail::Message::Head
ngl the "realization will take place" line is so dramatic. it's giving awakenings. 😭

🧚 About the body

Extends "About the body" in Mail::Message::Head.

  • $obj->guessBodySize() — the body size is defined in the Content-Length field. however, this field may not be known. in that case, a guess is made based on the known Lines field. when also that field is not known yet, undef is returned. Improves base, see "About the body" in Mail::Message::Head
  • $obj->isMultipart() — Inherited, see "About the body" in Mail::Message::Head

so: Content-Length first, then a lil guess from Lines, and if neither? undef. she's honest about not knowing 🙈

🌟 Internals

Extends "Internals" in Mail::Message::Head.

  • $obj->addNoRealize($field) — Inherited, see "Internals" in Mail::Message::Head
  • $obj->addOrderedFields($fields) — Inherited, see "Internals" in Mail::Message::Head
  • $obj->fileLocation() — Inherited, see "Internals" in Mail::Message::Head
  • $obj->load() — Inherited, see "Internals" in Mail::Message::Head
  • $obj->moveLocation($distance) — Inherited, see "Internals" in Mail::Message::Head
  • $obj->read($parser) — Inherited, see "Internals" in Mail::Message::Head
  • $obj->setNoRealize($field) — Inherited, see "Internals" in Mail::Message::Head

💀 Error handling

Extends "Error handling" in Mail::Message::Head.

  • $obj->AUTOLOAD() — Inherited, see "Error handling" in Mail::Reporter
  • $obj->notImplemented() — Inherited, see "Error handling" in Mail::Reporter

💜 Cleanup

Extends "Cleanup" in Mail::Message::Head.

  • $obj->DESTROY() — Inherited, see "Cleanup" in Mail::Reporter

⭐ DETAILS

Extends "DETAILS" in Mail::Message::Head.

🎀 DIAGNOSTICS

  • Error: class $package does not implement method $method. — Fatal error: the specific $package (or one of its superclasses) does not implement this method where it should. This message means that some other related classes do implement this method however the class at hand does not. Probably you should investigate this and probably inform the author of the package. Cast by notImplemented()
this one's a real one. if you catch this, something is genuinely broken — go investigate, and probably go tell the author of the package 🫶

🌈 SEE ALSO

This module is part of Mail-Box version 4.02, built on April 10, 2026. 🌸

Website: http://perl.overmeer.net/CPAN/

👑 LICENSE

For contributors see file ChangeLog.

This software is copyright (c) 2001-2026 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.

and that's the whole page bestie, no skips, no summaries, every single inherited line accounted for 💖 mwah 💋

built for perl v5.40.1, dated 2026-05-09, and yes, this is Mail::...:Subset(3pm) signing off — stay subset, stay slay 🎀✨

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