Class: BibTeX::Entry

Inherits:
Element show all
Extended by:
Forwardable
Includes:
Enumerable
Defined in:
lib/bibtex/entry.rb

Overview

Represents a regular BibTeX entry.

Defined Under Namespace

Classes: BibTeXMLConverter, CiteProcConverter, RDFConverter

Constant Summary collapse

REQUIRED_FIELDS =

Defines the required fields of the standard entry types

Hash.new([]).merge(
  article: %i[author title journal year],
  book: [%i[author editor], :title, :publisher, :year],
  booklet: [:title],
  conference: %i[author title booktitle year],
  inbook: [%i[author editor], :title, %i[chapter pages], :publisher, :year],
  incollection: %i[author title booktitle publisher year],
  inproceedings: %i[author title booktitle year],
  manual: [:title],
  mastersthesis: %i[author title school year],
  misc: [],
  phdthesis: %i[author title school year],
  proceedings: %i[title year],
  techreport: %i[author title institution year],
  unpublished: %i[author title note]
).freeze
FIELD_ALIASES =

Defines the default fallbacks for values defined in cross-references

{
  booktitle: :title
  # :editor => :author
}.freeze
NAME_FIELDS =
%i[author editor translator director producer composer].freeze
DATE_FIELDS =
%i[year month day date].freeze
MONTHS =
%i[jan feb mar apr may jun jul aug sep oct nov dec].freeze
MONTHS_FILTER =
Hash.new do |h, k|
  h[k] = case k.to_s.strip
         when /^(jan|feb|mar|apr|may|jun|jul|aug|sep|oct|nov|dec)/i
           Value.new(k.to_s[0, 3].downcase.to_sym)
         when /^\d\d?$/
           Value.new(MONTHS[k.to_i - 1] || k)
         else
           Value.new(k)
         end
end

Instance Attribute Summary collapse

Attributes inherited from Element

#bibliography

Instance Method Summary collapse

Methods inherited from Element

#inspect, #matches?, #meets?, #meets_all?, #meets_any?, parse, #to_json, #to_yaml

Constructor Details

#initialize(attributes = {}) {|_self| ... } ⇒ Entry

Creates a new instance. If a hash is given, the entry is populated accordingly.

Yields:

  • (_self)

Yield Parameters:

  • _self (BibTeX::Entry)

    the object that the method was called on



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# File 'lib/bibtex/entry.rb', line 72

def initialize(attributes = {})
  @fields = {}
  @key = nil

  self.type = attributes.delete(:bibtex_type) if attributes.key?(:bibtex_type)
  self.key = attributes.delete(:bibtex_key) if attributes.key?(:bibtex_key)

  add(attributes)

  yield self if block_given?
end

Dynamic Method Handling

This class handles dynamic methods through the method_missing method

#method_missing(name, *args, &block) ⇒ Object



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# File 'lib/bibtex/entry.rb', line 266

def method_missing(name, *args, &block)
  if fields.key?(name)
    fields[name]
  elsif name.to_s =~ /^(.+)=$/
    send(:add, Regexp.last_match(1).to_sym, args[0])
  elsif name =~ /^(?:convert|from)_([a-z]+)(!)?$/
    Regexp.last_match(2) ? convert!(Regexp.last_match(1), &block) : convert(Regexp.last_match(1), &block)
  elsif has_parent? && parent.provides?(name)
    parent.provide(name)
  else
    super
  end
end

Instance Attribute Details

#fieldsObject (readonly)

Returns the value of attribute fields.



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# File 'lib/bibtex/entry.rb', line 67

def fields
  @fields
end

#typeObject

Returns the value of attribute type.



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# File 'lib/bibtex/entry.rb', line 67

def type
  @type
end

Instance Method Details

#<=>(other) ⇒ Object



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# File 'lib/bibtex/entry.rb', line 587

def <=>(other)
  type != other.type ? type <=> other.type : key != other.key ? key <=> other.key : to_s <=> other.to_s
end

#[](name) ⇒ Object Also known as: get

Returns the value of the field with the given name. If the value is not defined and the entry has cross-reference, returns the cross-referenced value instead.



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# File 'lib/bibtex/entry.rb', line 309

def [](name)
  fields[name.to_sym] || parent&.provide(name)
end

#[]=(name, value) ⇒ Object

Adds a new field (name-value pair) to the entry. Returns the new value.



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# File 'lib/bibtex/entry.rb', line 321

def []=(name, value)
  add(name.to_sym, value)
end

#add(*arguments) ⇒ Object Also known as: <<

call-seq:

add(:author, "Edgar A. Poe")
add(:author, "Edgar A. Poe", :title, "The Raven")
add([:author, "Edgar A. Poe", :title, "The Raven"])
add(:author => "Edgar A. Poe", :title => "The Raven")
add(:author => Names.new(Name.new(:first => 'Edgar A.', :last => 'Poe')))

Adds a new field (name-value pair) or multiple fields to the entry. Returns the entry for chainability.



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# File 'lib/bibtex/entry.rb', line 334

def add(*arguments)
  Hash[*arguments.flatten].each_pair do |name, value|
    fields[name.to_sym] = Value.create(value)
  end

  self
end

#added_to_bibliography(bibliography) ⇒ Object

Called when the element was added to a bibliography.



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# File 'lib/bibtex/entry.rb', line 396

def added_to_bibliography(bibliography)
  super

  @key = register(key)

  %i[parse_names parse_months].each do |parser|
    send(parser) if bibliography.options[parser]
  end

  if bibliography.options.key?(:filter)
    [*bibliography.options[:filter]].each do |filter|
      convert!(filter)
    end
  end

  self
end

#aliasesObject

Returns the Entry’s field name aliases.



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# File 'lib/bibtex/entry.rb', line 142

def aliases
  @aliases ||= FIELD_ALIASES.dup
end

#childrenObject Also known as: cross_referenced_by

Returns a list of all entries in the Bibliography containing a cross-reference to this entry or [] if there are no references to this entry.



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# File 'lib/bibtex/entry.rb', line 536

def children
  bibliography&.q("@entry[crossref=#{key}]") || []
end

#contained?Boolean

Returns true if this entry is published inside a book, collection or journal

Returns:

  • (Boolean)


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# File 'lib/bibtex/entry.rb', line 555

def contained?
  has_field?(:container, :journal) ||
    has_field?(:booktitle) && get(:booktitle) != get(:title)
end

#container_titleObject



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# File 'lib/bibtex/entry.rb', line 542

def container_title
  get(:booktitle) || get(:journal) || get(:container)
end

#content(options = {}) ⇒ Object

Returns a string of all the entry’s fields.



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# File 'lib/bibtex/entry.rb', line 592

def content(options = {})
  fields.map { |k, _v| "#{k} = #{fields[k].to_s(options)}" }.join(",\n")
end

#convert(*filters, &block) ⇒ Object

Returns a duplicate entry with all values converted using the filter(s). If an optional block is given, only those values will be converted where the block returns true (the block will be called with each key-value pair).

See Also:



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# File 'lib/bibtex/entry.rb', line 572

def convert(*filters, &block)
  block_given? ? dup.convert!(*filters, &block) : dup.convert!(*filters)
end

#convert!(*filters) ⇒ Object

In-place variant of @see #convert



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# File 'lib/bibtex/entry.rb', line 577

def convert!(*filters)
  filters = filters.flatten.map { |f| Filters.resolve!(f) }

  fields.each_pair do |k, v|
    !block_given? || yield(k, v) ? v.convert!(*filters) : v
  end

  self
end

#dateObject



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# File 'lib/bibtex/entry.rb', line 478

def date
  get(:date) || get(:year)
end

#delete(name) ⇒ Object

Removes the field with a given name from the entry. Returns the value of the deleted field; nil if the field was not set.



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# File 'lib/bibtex/entry.rb', line 346

def delete(name)
  fields.delete(name.to_sym)
end

#digest(filter = []) ⇒ String

Creates the entry’s digest based on the passed-in filters.

The digest contains the type and all key-value pairs based on the passed in filter.

If a block is given, the computed digest will be passed to the block for post-processing (the entry itself will be passed as the second parameter).

Parameters:

  • the (<Symbol>)

    field names to use

Returns:

  • (String)

    the digest string

See Also:



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# File 'lib/bibtex/entry.rb', line 371

def digest(filter = [])
  names = field_names(filter)
  digest = type.to_s

  names.zip(values_at(*names)).each do |key, value|
    digest << "|#{key}:#{value}"
  end

  digest = yield(digest, self) if block_given?
  digest
end

#each(&block) ⇒ Object Also known as: each_pair

call-seq:

entry.each      { |key, value| block } -> entry
entry.each_pair { |key, value| block } -> entry
entry.each                             -> an_enumerator
entry.each_pair                        -> an_enumerator

Calls block once for each key in entry, passing the key-value pair as parameters.

If no block is given, an enumerator is returned instead.



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# File 'lib/bibtex/entry.rb', line 130

def each(&block)
  if block_given?
    fields.each(&block)
    self
  else
    to_enum
  end
end

#fetch(name, default = nil) ⇒ Object



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# File 'lib/bibtex/entry.rb', line 315

def fetch(name, default = nil)
  get(name) || (block_given? ? yield(name) : default)
end

#field_names(filter = [], include_inherited = true) ⇒ Object

Returns a sorted list of the Entry’s field names. If a filter is passed as argument, returns all field names that are also defined by the filter. If the filter is empty, returns all field names.

If the second optional argument is true (default) and the Entry contains a cross-reference, the list will include all inherited fields.



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# File 'lib/bibtex/entry.rb', line 244

def field_names(filter = [], include_inherited = true)
  names = fields.keys

  names.concat(inherited_fields) if include_inherited && has_parent?

  names &= filter.map(&:to_sym) unless filter.empty?

  names.sort!
  names
end

#has_children?Boolean Also known as: cross_referenced?

Returns true if the entry is cross-referenced by another entry in the Bibliography.

Returns:

  • (Boolean)


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# File 'lib/bibtex/entry.rb', line 527

def has_children?
  !children.empty?
end

#has_field?(*names) ⇒ Boolean Also known as: field?

Returns:

  • (Boolean)


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# File 'lib/bibtex/entry.rb', line 187

def has_field?(*names)
  names.flatten.any? do |name|
    name.respond_to?(:to_sym) ? fields.key?(name.to_sym) : false
  end
end

#has_parent?Boolean Also known as: has_cross_reference?

Returns true if the Entry has a valid cross-reference in the Bibliography.

Returns:

  • (Boolean)


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# File 'lib/bibtex/entry.rb', line 503

def has_parent?
  !parent.nil?
end

#has_type?(type) ⇒ Boolean Also known as: type?

Returns:

  • (Boolean)


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# File 'lib/bibtex/entry.rb', line 181

def has_type?(type)
  type.to_s.match(/^(?:entry|\*)$/i) || @type.casecmp?(type.to_sym) || super
end

#identifierObject



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# File 'lib/bibtex/entry.rb', line 383

def identifier
  if provides?(:doi)
    "info:doi/#{get(:doi)}"
  elsif provides?(:isbn)
    "urn:isbn:#{get(:isbn)}"
  elsif provides?(:issn)
    "urn:issn:#{get(:issn)}"
  else
    "urn:bibtex:#{key}"
  end
end

#inherited_fieldsObject

Returns a sorted list of all field names referenced by this Entry’s cross-reference.



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# File 'lib/bibtex/entry.rb', line 256

def inherited_fields
  return [] unless has_parent?

  names = parent.fields.keys - fields.keys
  names.concat(parent.aliases.select { |_k, v| parent.has_field?(v) }.keys)
  names.sort!

  names
end

#inherits?(*names) ⇒ Boolean

Returns:

  • (Boolean)


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# File 'lib/bibtex/entry.rb', line 195

def inherits?(*names)
  names.flatten.any? do |name|
    !has_field(name) && has_parent? && parent.provides?(name)
  end
end

#initialize_copy(other) ⇒ Object



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# File 'lib/bibtex/entry.rb', line 84

def initialize_copy(other)
  @fields = {}

  self.type = other.type
  self.key = other.key

  add(other.fields)
end

#joinObject



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# File 'lib/bibtex/entry.rb', line 446

def join
  fields.values.each(&:join)
  self
end

#keyObject Also known as: id



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# File 'lib/bibtex/entry.rb', line 165

def key
  if @key.nil? || @key.empty?
    @key = default_key
  else
    @key
  end
end

#key=(key) ⇒ Object Also known as: id=

Sets the Entry’s key. If the Entry is currently registered with a Bibliography, re-registers the Entry with the new key; note that this may change the key value if another Entry is already regsitered with the same key.

Returns the new key.



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# File 'lib/bibtex/entry.rb', line 152

def key=(key)
  key = key.to_s

  if registered?
    bibliography.entries.delete(@key)
    key = register(key)
  end

  @key = key
rescue StandardError => e
  raise BibTeXError, "failed to set key to #{key.inspect}: #{e.message}"
end

#merge(other, filter = field_names) ⇒ Object



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# File 'lib/bibtex/entry.rb', line 93

def merge(other, filter = field_names)
  dup.merge!(other, filter)
end

#merge!(other, filter = field_names) ⇒ Object

Raises:

  • (InvalidArgument)


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# File 'lib/bibtex/entry.rb', line 97

def merge!(other, filter = field_names)
  raise InvalidArgument, "failed to merge entries: type mismatch: #{type} #{other.type}" unless
    type == other.type

  other.each do |name, value|
    if has_field?(name)
      get(name).merge!(value) if filter.include?(name)
    else
      add name, value.dup
    end
  end

  self
end

#month=(month) ⇒ Object



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# File 'lib/bibtex/entry.rb', line 451

def month=(month)
  fields[:month] = month
ensure
  parse_month
end

#month_numericObject



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# File 'lib/bibtex/entry.rb', line 457

def month_numeric
  return unless has_field?(:month)
  return unless (num = MONTHS.index fields[:month].to_sym)

  num.succ
end

#namesObject

Returns a list of all names (authors, editors, translators).



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# File 'lib/bibtex/entry.rb', line 498

def names
  NAME_FIELDS.map { |k| has_field?(k) ? @fields[k].tokens : nil }.flatten.compact
end

#pages_fromObject



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# File 'lib/bibtex/entry.rb', line 546

def pages_from
  fetch(:pages, '').split(/\D+/)[0]
end

#pages_toObject



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# File 'lib/bibtex/entry.rb', line 550

def pages_to
  fetch(:pages, '').split(/\D+/)[-1]
end

#parentObject Also known as: cross_reference

Returns the cross-referenced Entry from the Bibliography or nil if this Entry does define a cross-reference.



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# File 'lib/bibtex/entry.rb', line 519

def parent
  bibliography && bibliography[fields[:crossref]]
end

#parent_missing?Boolean Also known as: cross_reference_missing?

Returns true if the Entry cross-references an Entry which is not registered in the current Bibliography.

Returns:

  • (Boolean)


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# File 'lib/bibtex/entry.rb', line 511

def parent_missing?
  has_field?(:crossref) && !has_parent?
end

#parse_monthObject Also known as: parse_months



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# File 'lib/bibtex/entry.rb', line 464

def parse_month
  fields.delete(:month_numeric)
  return unless has_field?(:month)

  fields[:month] = MONTHS_FILTER[fields[:month]]

  numeric = MONTHS.index(fields[:month].to_sym)
  fields[:month_numeric] = Value.new(numeric.succ) if numeric

  self
end

#parse_namesObject

Parses all name values of the entry. Tries to replace and join the value prior to parsing.



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# File 'lib/bibtex/entry.rb', line 484

def parse_names
  strings = bibliography ? bibliography.strings.values : []

  NAME_FIELDS.each do |key|
    if name = fields[key]
      name = name.dup.replace(strings).join.to_name
      fields[key] = name unless name.nil?
    end
  end

  self
end

#provide(name) ⇒ Object

Returns the field value referenced by the passed-in name. For example, this will return the ‘title’ value for ‘booktitle’ if a corresponding alias is defined.



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# File 'lib/bibtex/entry.rb', line 219

def provide(name)
  return nil unless name.respond_to?(:to_sym)

  name = name.to_sym
  fields[name] || fields[aliases[name]]
end

#provides?(*names) ⇒ Boolean

Returns true if the Entry has a field (or alias) for any of the passed-in names.

Returns:

  • (Boolean)


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# File 'lib/bibtex/entry.rb', line 202

def provides?(*names)
  names.flatten.any? do |name|
    if name.respond_to?(:to_sym)
      has_field?(name) || has_field?(aliases[name.to_sym])
    else
      false
    end
  end
end

#provides_or_inherits?(*names) ⇒ Boolean

Returns:

  • (Boolean)


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# File 'lib/bibtex/entry.rb', line 212

def provides_or_inherits?(*names)
  provides?(names) || inherits?(names)
end

#register(key) ⇒ Object

Registers this Entry in the associated Bibliographies entries hash. This method may change the Entry’s key, if another entry is already registered with the current key.

Returns the key or nil if the Entry is not associated with a Bibliography.



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# File 'lib/bibtex/entry.rb', line 431

def register(key)
  return nil if bibliography.nil?

  k = key.dup
  k.succ! while bibliography.key?(k)
  bibliography.entries[k] = self
  k
end

#registered?Boolean

Returns true if the Entry is currently registered with the associated Bibliography.

Returns:

  • (Boolean)


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# File 'lib/bibtex/entry.rb', line 422

def registered?
  !!(bibliography && bibliography.entries[key].equal?(self))
end

#removed_from_bibliography(bibliography) ⇒ Object

Called when the element was removed from a bibliography.



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# File 'lib/bibtex/entry.rb', line 415

def removed_from_bibliography(bibliography)
  super
  bibliography.entries.delete(key)
  self
end

#rename(*arguments) ⇒ Object Also known as: rename_fields

Returns a copy of the Entry with all the field names renamed.



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# File 'lib/bibtex/entry.rb', line 287

def rename(*arguments)
  dup.rename!(*arguments)
end

#rename!(*arguments) ⇒ Object Also known as: rename_fields!

Renames the given field names unless a field with the new name already exists.



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# File 'lib/bibtex/entry.rb', line 293

def rename!(*arguments)
  Hash[*arguments.flatten].each_pair do |from, to|
    if fields.key?(from) && !fields.key?(to)
      fields[to] = fields[from]
      fields.delete(from)
    end
  end
  self
end

#replace(*arguments) ⇒ Object



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# File 'lib/bibtex/entry.rb', line 440

def replace(*arguments)
  arguments = bibliography.q('@string') if arguments.empty?
  fields.values.each { |v| v.replace(*arguments) }
  self
end

#respond_to?(method, include_all = false) ⇒ Boolean

Returns:

  • (Boolean)


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# File 'lib/bibtex/entry.rb', line 280

def respond_to?(method, include_all = false)
  provides?(method.to_sym) || method.to_s.match(/=$/) ||
    method =~ /^(?:convert|from)_([a-z]+)(!)?$/ ||
    (has_parent? && parent.respond_to?(method, include_all)) || super
end

#save_inherited_fieldsObject

If the Entry has a cross-reference, copies all referenced all inherited values from the parent.

Returns the Entry.



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# File 'lib/bibtex/entry.rb', line 230

def save_inherited_fields
  inherited_fields.each do |name|
    fields[name] = parent.provide(name)
  end

  self
end

#to_citeproc(options = {}) ⇒ Object



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# File 'lib/bibtex/entry.rb', line 609

def to_citeproc(options = {})
  CiteProcConverter.convert(self, options)
end

#to_hash(options = {}) ⇒ Object



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# File 'lib/bibtex/entry.rb', line 602

def to_hash(options = {})
  options[:quotes] ||= %w[{ }]
  hash = { bibtex_key: key, bibtex_type: type }
  each_pair { |k, v| hash[k] = v.to_s(options) }
  hash
end

#to_rdf(_options = {}) ⇒ Object Also known as: to_bibo

Returns a RDF::Graph representation of the entry using the BIBO ontology.



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# File 'lib/bibtex/entry.rb', line 618

def to_rdf(_options = {})
  if defined?(::RDF)
    RDFConverter.convert(self)
  else
    BibTeX.log.error 'Please `gem install rdf` for RDF support.'
  end
end

#to_s(options = {}) ⇒ Object

Returns a string representation of the entry.



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# File 'lib/bibtex/entry.rb', line 597

def to_s(options = {})
  options[:quotes] ||= %w[{ }]
  ["@#{type}{#{key},", content(options).gsub(/^/, '  '), "}\n"].join("\n")
end

#to_xml(options = {}) ⇒ Object



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# File 'lib/bibtex/entry.rb', line 613

def to_xml(options = {})
  BibTeXMLConverter.convert(self, options)
end

#update(fields) ⇒ Object



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# File 'lib/bibtex/entry.rb', line 112

def update(fields)
  fields.each do |name, value|
    add name, value
  end

  self
end

#valid?Boolean

Returns false if the entry is one of the standard entry types and does not have definitions of all the required fields for that type.

Returns:

  • (Boolean)


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# File 'lib/bibtex/entry.rb', line 352

def valid?
  REQUIRED_FIELDS[type].all? do |f|
    f.is_a?(Array) ? !(f & fields.keys).empty? : !fields[f].nil?
  end
end

#values_at(*arguments) ⇒ Object

Returns an array containing the values associated with the given keys.



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# File 'lib/bibtex/entry.rb', line 561

def values_at(*arguments)
  arguments.map do |key|
    get key
  end
end

#yearObject



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# File 'lib/bibtex/entry.rb', line 628

def year
  return fields[:year] if has_field?(:year)
  return unless has_field?(:date)

  fields[:date].to_s[/\d{4}/]
end