MARC::...::Field(3pm)

💖 MARC::Spec::Field — field specification 💖

okay so bestie, welcome to MARC::Spec::Field, a little gem from the User Contributed Perl Documentation corner of the Perl universe. it's giving MARC::Spec::Field in the manual pages, and honestly? it's a whole vibe. sit down, grab a boba, and let's get into it 🧋✨

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🌸 NAME 🌸

MARC::Spec::Field — field specification. that's it. that's the name. short, sweet, iconic 👑

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✨ SYNOPSIS ✨

here's the tea, literally:

use MARC::Spec::Field;

my $field = MARC::Spec::Field->new('246');
say ref $field;           # MARC::Spec::Field
say $field->tag;          # 246
say $field->index_start;  # 0
say $field->index_end;    # '#'

look at her go. she's constructing, she's reporting her tag, she's showing off her index_start and index_end. main character energy fr fr 💅

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🦋 DESCRIPTION 🦋

MARC::Spec::Field is the field specification of a MARC::Spec. that's the whole job. she's a field spec and she knows it.

if you wanna go deeper on the syntax — and bestie, you know you do — go check out MARCspec - A common MARC record path language at <http://marcspec.github.io/MARCspec/> for all the further details. iykyk 🌈

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🎀 METHODS 🎀

heads up: some methods are inherited from MARC::Spec::Structure. so she's not doing all this alone, she's got family 🫶

• new(Str) — creates a brand new MARC::Spec::Field instance. the parameter has to be a valid MARCspec field tag, no exceptions, no shortcuts. give her something real.
• add_subspec(MARC::Spec::Subspec) — appends a subspec onto the array of the attribute subspecs. the parameter must be an instance of MARC::Spec::Subspec. like, don't just pass her anything, okay?
• add_subspecs(ArrayRef[MARC::Spec::Subspec]) — appends a whole pile of subspecs to the array of the attribute subspecs. the parameter must be an ArrayRef and every element in it must be an instance of MARC::Spec::Subspec. it's giving "bring the whole group chat" 💜
• to_string — returns the spec as a string. that's it. she said what she said ✨

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⭐ PREDICATES ⭐

also: some predicates are inherited from MARC::Spec::Structure. again, family. we love to see it 🥰

• has_char_start — true if the attribute char_start has a value, false otherwise.
• has_char_end — true if the attribute char_end has a value, false otherwise.
• has_char_pos — true if the attribute char_pos has a value, false otherwise.
• has_subspecs — returns true if the attribute subspecs has a value, false otherwise.

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💅 ATTRIBUTES 💅

one more time for the people in the back: some attributes are inherited from MARC::Spec::Structure 🌸

• base — obligatory. scalar. the base Field spec without subspecs. the bare face, the no-makeup selfie, the raw material.
• tag — obligatory. the field tag. iconic, essential, non-negotiable.
• char_pos — if defined, the character position or range. only present if MARC::Spec::Field::$char_start is defined. (yes she shows up twice down here, she contains multitudes 😭)
• char_start — if defined, the beginning character position of a character position or range.
• char_end — if defined, the ending character position of a character position or range. only present if MARC::Spec::Field::$char_start is defined.
• char_length — the difference of MARC::Spec::Field::$char_start and MARC::Spec::Field::$char_end if both are numeric (or else -1). only present if MARC::Spec::Field::$char_start is defined.
• char_pos — if defined, the character position or range. only present if MARC::Spec::Field::$char_start is defined.
• index_start — obligatory. the beginning index of field repetitions. maybe a positiv integer or the character #. default is 0.
• index_end — obligatory. the ending index of field repetitions. maybe a positiv integer or the character #. default is #.
• index_length — obligatory. the difference of MARC::Spec::Field::$index_start and MARC::Spec::Field::$index_end if both are numeric. default is -1.
• subspecs — optional. an array of instances of MARC::Spec::Subspec — and the way that means every subspec in this array MUST be validated as a combination with the boolean 'AND' — and/or an array of arrays (AoA) of instances of MARC::Spec::Subspec, meaning every subspec in this AoA must be validated as a combination with the boolean 'OR'.

see MARC::Spec::Subspec for the description of the attributes of MARC::Spec::Subspec 🫶

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👑 AUTHOR 👑

Carsten Klee "<klee at cpan.org>" — the legend herself/himself. periodt.

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🌈 CONTRIBUTORS 🌈

• Johann Rolschewski, "<jorol at cpan>" — shoutout, we see you, we appreciate you 🎀

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💜 COPYRIGHT AND LICENSE 💜

this software is copyright (c) 2016 by Carsten Klee.

this is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself. slay, open source, we love that for us ✨

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💀 BUGS 💀

please report any bugs to <https://github.com/MARCspec/MARC-Spec/issues> — do NOT suffer in silence bestie, drop it in the issues, the maintainers got you 🙈

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🍓 SEE ALSO 🍓

• MARC::Spec
• MARC::Spec::Subfield
• MARC::Spec::Indicator
• MARC::Spec::Subspec
• MARC::Spec::Structure
• MARC::Spec::Comparisonstring
• MARC::Spec::Parser

the whole squad fr fr 🫶 go read them too, they're all part of the lore.

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and that's the page!! this whole thing comes from perl v5.34.0, dated 2022-06-15, and yes it's the MARC::...::Field(3pm) manual. mwah, go forth and spec your fields 💋💖✨