Class: RDF::Vocabulary

Inherits:
Object
  • Object
show all
Extended by:
Enumerable
Defined in:
lib/rdf/vocabulary.rb,
lib/rdf/vocab/writer.rb

Overview

A Vocabulary represents an RDFS or OWL vocabulary.

A Vocabulary can also serve as a Domain Specific Language (DSL) for generating an RDF Graph definition for the vocabulary (see #to_enum).

Defining a vocabulary using the DSL

Vocabularies can be defined based on Vocabulary or StrictVocabulary using a simple Domain Specific Language (DSL).

  • Ontology information for the vocabulary itself can be specified using the Vocabulary.ontology method.

  • Terms of the vocabulary are specified using either property or term (alias), with the attributes of the term listed in a hash. See Vocabulary.property for description of the hash. Term attributes become properties of the associated Term (see Term#attributes).

Note that, by default, the prefix associated with the vocabulary for forming and interpreting PNames is created from the class name of the vocabulary. See Vocabulary.__prefix__= for overriding this at runtime.

The simplest way to generate a DSL representation of a vocabulary is using Writer given an Graph representation of the vocabulary.

Vocabularies:

The following vocabularies are pre-defined for your convenience:

  • RDF - Resource Description Framework (RDF)

  • OWL - Web Ontology Language (OWL)

  • RDFS - RDF Schema (RDFS)

  • XSD - XML Schema (XSD)

Other vocabularies are defined in the rdf-vocab gem

Examples:

Using pre-defined RDF vocabularies

include RDF

RDF.type      #=> RDF::URI("http://www.w3.org/1999/02/22-rdf-syntax-ns#type")
RDFS.seeAlso  #=> RDF::URI("http://www.w3.org/2000/01/rdf-schema#seeAlso")
OWL.sameAs    #=> RDF::URI("http://www.w3.org/2002/07/owl#sameAs")
XSD.dateTime  #=> RDF::URI("http://www.w3.org/2001/XMLSchema#dateTime")

Using ad-hoc RDF vocabularies

foaf = RDF::Vocabulary.new("http://xmlns.com/foaf/0.1/")
foaf.knows    #=> RDF::URI("http://xmlns.com/foaf/0.1/knows")
foaf[:name]   #=> RDF::URI("http://xmlns.com/foaf/0.1/name")
foaf['mbox']  #=> RDF::URI("http://xmlns.com/foaf/0.1/mbox")

Defining a simple vocabulary

EX = Class.new(RDF::StrictVocabulay("http://example/ns#")) do
  # Ontology definition
  ontology :"http://example/ns#",
    label: "The RDF Example Vocablary",
    type: "http://www.w3.org/2002/07/owl#Ontology"

  # Class definitions
  term :Class,
    label: "My Class",
    comment: "Good to use as an example",
    type: "rdfs:Class",
    subClassOf: "http://example/SuperClass",
    "ex:prop": "Some annotation property not having a shortcut"

  # Property definitions
  property :prop,
    comment: "A description of the property",
    label: "property",
    domain: "http://example/ns#Class",
    range: "rdfs:Literal",
    isDefinedBy: %(ex:),
    type: "rdf:Property"
end

Method calls are converted to the typical RDF camelcase convention

foaf = RDF::Vocabulary.new("http://xmlns.com/foaf/0.1/")
foaf.family_name    #=> RDF::URI("http://xmlns.com/foaf/0.1/familyName")
owl.same_as         #=> RDF::URI("http://www.w3.org/2002/07/owl#sameAs")
# []-style access is left as is
foaf['family_name'] #=> RDF::URI("http://xmlns.com/foaf/0.1/family_name")
foaf[:family_name]  #=> RDF::URI("http://xmlns.com/foaf/0.1/family_name")

Generating RDF from a vocabulary definition

graph = RDF::Graph.new << RDF::RDFS.to_enum
graph.dump(:ntriples)

See Also:

Direct Known Subclasses

StrictVocabulary, XSD

Defined Under Namespace

Modules: Term Classes: Format, Writer

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(uri) ⇒ Vocabulary

Returns a new instance of Vocabulary.

Parameters:



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# File 'lib/rdf/vocabulary.rb', line 673

def initialize(uri)
  @uri = case uri
    when RDF::URI then uri.to_s
    else RDF::URI.parse(uri.to_s) ? uri.to_s : nil
  end
end

Dynamic Method Handling

This class handles dynamic methods through the method_missing method

#method_missing(property, *args, &block) ⇒ Object (protected) 



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# File 'lib/rdf/vocabulary.rb', line 723

def method_missing(property, *args, &block)
  property = self.class.camelize(property.to_s)
  if %w(to_ary).include?(property.to_s)
    super
  elsif args.empty?
    self[property]
  else
    super
  end
end

Class Method Details

.[](property) ⇒ RDF::URI

Returns the URI for the term property in this vocabulary.

Parameters:

Returns:



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# File 'lib/rdf/vocabulary.rb', line 405

def [](property)
  if props.key?(property.to_sym)
    props[property.to_sym]
  else
    Term.intern([to_s, property.to_s].join(''), vocab: self, attributes: {})
  end
end

.__prefix__ ⇒ Symbol

Returns a suggested vocabulary prefix for this vocabulary class.

Returns:

  • (Symbol)

Since:

  • 0.3.0



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# File 'lib/rdf/vocabulary.rb', line 609

def __prefix__
  instance_variable_defined?(:@__prefix__) ?
    @__prefix__ :
    __name__.split('::').last.downcase.to_sym
end

.__prefix__=(prefix) ⇒ Symbol

Sets the vocabulary prefix to use for this vocabulary..

Examples:

Overriding a standard vocabulary prefix.

RDF::Vocab::DC.__prefix__ = :dcterms
RDF::Vocab::DC.title.pname #=> 'dcterms:title'

Parameters:

  • prefix (Symbol)

Returns:

  • (Symbol)

Since:

  • 3.2.3



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# File 'lib/rdf/vocabulary.rb', line 625

def __prefix__=(prefix)
  params = RDF::Vocabulary.vocab_map[__prefix__]
  @__prefix__ = prefix.to_sym
  RDF::Vocabulary.register(@__prefix__, self, **params)
  @__prefix__
end

.camelize(str) ⇒ Object (protected) 



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# File 'lib/rdf/vocabulary.rb', line 734

def self.camelize(str)
  str.split('_').inject([]) do |buffer, e| 
    buffer.push(buffer.empty? ? e : e.capitalize)
  end.join
end

.each {|klass| ... } ⇒ Enumerator

Enumerates known RDF vocabulary classes.

Yields:

  • (klass)

Yield Parameters:

  • klass (Class)

Returns:

  • (Enumerator) 


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# File 'lib/rdf/vocabulary.rb', line 93

def each(&block)
  if self.equal?(Vocabulary)
    if instance_variable_defined?(:@vocabs) && @vocabs
      @vocabs.select(&:name).each(&block)
    else
      # This is needed since all vocabulary classes are defined using
      # Ruby's autoloading facility, meaning that `@@subclasses` will be
      # empty until each subclass has been touched or require'd.
      RDF::VOCABS.each { |v, p| RDF.const_get(p[:class_name].to_sym) unless v == :rdf }
      @@subclasses.select(&:name).each(&block)
    end
  else
    __properties__.each(&block)
  end
end

.each_statement {|| ... } ⇒ Object

Enumerate each statement constructed from the defined vocabulary terms

If a property value is known to be a URI, or expands to a URI, the object is a URI, otherwise, it will be a Literal.

Yields:

  • statement

Yield Parameters:



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# File 'lib/rdf/vocabulary.rb', line 468

def each_statement(&block)
  props.each do |name, subject|
    subject.each_statement(&block)
  end

  # Also include the ontology, if it's not also a property
  @ontology.each_statement(&block) if self.ontology && self.ontology != self
end

.enum_for(method = :each_statement, *args) ⇒ RDF::Enumerable::Enumerator Also known as: to_enum

Return an enumerator over Statement defined for this vocabulary.

Returns:

See Also:

  • Object#enum_for


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# File 'lib/rdf/vocabulary.rb', line 452

def enum_for(method = :each_statement, *args)
  # Ensure that enumerators are, themselves, queryable
  this = self
  Enumerable::Enumerator.new do |yielder|
    this.send(method, *args) {|*y| yielder << (y.length > 1 ? y : y.first)}
  end
end

.expand_pname(pname) ⇒ Term

Attempt to expand a Compact IRI/PName using loaded vocabularies

The local-part of the PName will will have reserved character escapes unescaped.

Parameters:

  • pname (String, #to_s)

Returns:

Raises:

  • (KeyError) —

    if pname suffix not found in identified vocabulary.

  • (ArgumentError) —

    if resulting URI is not valid



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# File 'lib/rdf/vocabulary.rb', line 346

def expand_pname(pname)
  return pname unless pname.is_a?(String) || pname.is_a?(Symbol)
  prefix, suffix = pname.to_s.split(":", 2)
  # Unescape escaped PN_ESCAPE_CHARS
  if suffix.match?(RDF::URI::PN_ESCAPES)
    suffix = suffix.gsub(RDF::URI::PN_ESCAPES) {|matched| matched[1..-1]}
  end
  if prefix == "rdf"
    RDF[suffix]
  elsif vocab_detail = RDF::Vocabulary.vocab_map[prefix.to_sym]
    vocab = vocab_detail[:class] ||
      RDF::Vocabulary.from_sym(vocab_detail[:class_name])
    suffix.to_s.empty? ? vocab.to_uri : vocab[suffix]
  else
    (RDF::Vocabulary.find_term(pname) rescue nil) || RDF::URI(pname, validate: true)
  end
end

.find(uri) ⇒ Vocabulary

Return the Vocabulary associated with a URI. Allows the trailing ‘/’ or ‘#’ to be excluded

Parameters:

Returns:



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# File 'lib/rdf/vocabulary.rb', line 369

def find(uri)
  uri = RDF::URI(uri) if uri.is_a?(String)
  return nil unless uri.uri? && uri.valid?
  RDF::Vocabulary.detect do |v|
    if uri.length >= v.to_uri.length
      uri.start_with?(v.to_uri)
    else
      v.to_uri.to_s.sub(%r([/#]$), '') == uri.to_s
    end
  end
end

.find_term(uri) ⇒ Vocabulary::Term

Return the Vocabulary term associated with a URI

Parameters:

  • uri (RDF::URI, String) —

    If uri has is a pname in a locded vocabulary, the suffix portion of the PName will have escape characters unescaped before resolving against the vocabulary.

Returns:



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# File 'lib/rdf/vocabulary.rb', line 387

def find_term(uri)
  uri = RDF::URI(uri)
  return uri if uri.is_a?(Vocabulary::Term)
  if vocab = find(uri)
    if vocab.ontology == uri
      vocab.ontology
    else
      suffix = uri.to_s[vocab.to_uri.to_s.length..-1].to_s
      vocab[suffix]
    end
  end
end

.from_graph(graph, url: nil, class_name: nil, extra: nil) ⇒ RDF::Vocabulary

Create a vocabulary from a graph or enumerable

Parameters:

  • graph (RDF::Enumerable)
  • url (URI, #to_s) (defaults to: nil)
  • class_name (RDF::Vocabulary, String) (defaults to: nil) —

    The class_name associated with the vocabulary, used for creating the class name of the vocabulary. This will create a new class named with a top-level constant based on class_name. If given an existing vocabulary, it replaces the existing definitions for that vocabulary with those from the graph.

  • extra (Array<Symbol>, Hash{Symbol => Hash}) (defaults to: nil) —

    Extra terms to add to the vocabulary. In the first form, it is an array of symbols, for which terms are created. In the second, it is a Hash mapping symbols to property attributes, as described in property.

Returns:



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# File 'lib/rdf/vocabulary.rb', line 495

def from_graph(graph, url: nil, class_name: nil, extra: nil)
  vocab = case class_name
  when RDF::Vocabulary
    class_name.instance_variable_set(:@ontology, nil)
    class_name.instance_variable_set(:@properties, nil)
    class_name
  when String
    Object.const_set(class_name, Class.new(self.create(url)))
  else
    Class.new(self.create(url))
  end

  ont_url = url.to_s.sub(%r([/#]$), '')
  term_defs = {}
  embedded_defs = {}
  graph.each do |statement|
    #next unless statement.subject.uri?
    if statement.subject.start_with?(url) || statement.subject == ont_url
      name = statement.subject.to_s[url.to_s.length..-1].to_s
      term = (term_defs[name.to_sym] ||= {})
    else
      # subject is not a URI or is not associated with the vocabulary
      term = (embedded_defs[statement.subject] ||= {})
    end

    key = Term::URI_ATTRs.fetch(statement.predicate) do
      statement.predicate.to_s.to_sym
    end

    (term[key] ||= []) << statement.object
  end

  # Create extra terms
  term_defs = case extra
  when Array
    extra.inject({}) {|memo, s| memo[s.to_sym] = {}; memo}.merge(term_defs)
  when Hash
    extra.merge(term_defs)
  else
    term_defs
  end

  # Pass over embedded_defs with anonymous references, once
  embedded_defs.each do |term, attributes|
    attributes.each do |ak, avs|
      # Turn embedded BNodes into either their Term definition or a List
      avs = [avs] unless avs.is_a?(Array)
      attributes[ak] = avs.map do |av|
        l = RDF::List.new(subject: av, graph: graph)
        if l.valid?
          RDF::List.new(subject: av) do |nl|
            l.each do |lv|
              nl << (embedded_defs[lv] ? Term.new(vocab: vocab, attributes: embedded_defs[lv]) : lv)
            end
          end
        elsif av.is_a?(RDF::Node)
          Term.new(vocab: vocab, attributes: embedded_defs[av]) if embedded_defs[av]
        else
          av
        end
      end.compact
    end
  end

  term_defs.each do |term, attributes|
    # Turn embedded BNodes into either their Term definition or a List
    attributes.each do |ak, avs|
      attributes[ak] = avs.is_a?(Array) ? (avs.map do |av|
        l = RDF::List.new(subject: av, graph: graph)
        if l.valid?
          RDF::List.new(subject: av) do |nl|
            l.each do |lv|
              nl << (embedded_defs[lv] ? Term.new(vocab: vocab, attributes: embedded_defs[lv]) : lv)
            end
          end
        elsif av.is_a?(RDF::Node)
          Term.new(vocab: vocab, attributes: embedded_defs[av]) if embedded_defs[av]
        else
          av
        end
      end).compact : avs
    end

    if term == :""
      vocab.__ontology__ vocab, attributes
    else
      vocab.__property__ term, attributes
    end
  end

  vocab
end

.from_sym(sym) ⇒ RDF::Vocabulary

Return the vocabulary based on it’s class_name symbol

Parameters:

  • sym (Symbol)

Returns:



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# File 'lib/rdf/vocabulary.rb', line 126

def from_sym(sym)
  RDF.const_get(sym.to_sym)
end

.imported_from ⇒ Array<RDF::Vocabulary>

List of vocabularies which import this vocabulary

Returns:



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# File 'lib/rdf/vocabulary.rb', line 431

def imported_from
  @imported_from ||= begin
    RDF::Vocabulary.select {|v| v.__imports__.include?(self)}
  end
end

.imports ⇒ Array<RDF::Vocabulary> Also known as: __imports__

Note:

the alias __imports__ guards against RDF::OWL.imports returning a term, rather than an array of vocabularies

List of vocabularies this vocabulary owl:imports

Returns:



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# File 'lib/rdf/vocabulary.rb', line 418

def imports
  return [] unless self.ontology
  @imports ||= begin
    Array(self.ontology.properties[:"http://www.w3.org/2002/07/owl#imports"]).compact
  rescue KeyError
    []
  end
end

.inspect ⇒ String

Returns a developer-friendly representation of this vocabulary class.

Returns:

  • (String) 


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# File 'lib/rdf/vocabulary.rb', line 592

def inspect
  if self == Vocabulary
    self.to_s
  else
    sprintf("%s(%s)", superclass.to_s, to_s)
  end
end

.limit_vocabs(*vocabs) ⇒ Array<RDF::Vocabulary>

Limits iteration over vocabularies to just those selected

Examples:

limit to set of vocabularies by symbol

RDF::Vocabulary.limit_vocabs(:rdf, :rdfs
RDF::Vocabulary.find_term('http://www.w3.org/2000/01/rdf-schema#Resource').pname
# => 'rdfs:Resource'

limit to set of vocabularies by class name

RDF::Vocabulary.limit_vocabs(RDF::RDFV, RDF::RDFS)
RDF::Vocabulary.find_term('http://www.w3.org/2000/01/rdf-schema#Resource').pname
# => 'rdfs:Resource'

Parameters:

  • vocabs (Array<symbol, RDF::Vocabulary>) —

    A list of vocabularies (symbols or classes) which may be returned by each. Also limits vocabularies that will be inspeced for other methods. Set to nil, or an empty array to reset.

Returns:



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# File 'lib/rdf/vocabulary.rb', line 179

def limit_vocabs(*vocabs)
  @vocabs = if Array(vocabs).empty?
    nil
  else
    vocabs.map do |vocab|
      vocab = :rdfv if vocab == :rdf
      vocab.is_a?(Symbol) && RDF::VOCABS.key?(vocab) ?
        RDF.const_get(RDF::VOCABS[vocab][:class_name].to_sym) :
        vocab
    end.compact
  end
end

.list(*values) ⇒ RDF::List (protected)

Create a list of terms

Parameters:

  • values (Array<String>) —

    Each value treated as a URI or PName

Returns:



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# File 'lib/rdf/vocabulary.rb', line 656

def list(*values)
  RDF::List[*values.map {|v| expand_pname(v) rescue RDF::Literal(v)}]
end

.method_missing(property, *args, &block) ⇒ Object (protected) 



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# File 'lib/rdf/vocabulary.rb', line 643

def method_missing(property, *args, &block)
  property = RDF::Vocabulary.camelize(property.to_s)
  if args.empty? && !to_s.empty?
    Term.intern([to_s, property.to_s].join(''), vocab: self, attributes: {})
  else
    super
  end
end

.ontology ⇒ RDF::Vocabulary::Term .ontology(name, options) ⇒ RDF::Vocabulary::Term Also known as: __ontology__

Note:

If the ontology URI has the vocabulary namespace URI as a prefix, it may also be defined using #property or #term

Overloads:

  • .ontology ⇒ RDF::Vocabulary::Term

    Returns the ontology definition of the current vocabulary as a term.

    Returns:

  • .ontology(name, options) ⇒ RDF::Vocabulary::Term

    Defines the vocabulary ontology.

    Parameters:

    • uri (String, #to_s) —

      The URI of the ontology.

    • options (Hash{Symbol => Object}) —

      See property

    • options (Hash{Symbol=>String,Array<String,Term>}) —

      Any other values are expected to expands to a URI using built-in vocabulary prefixes. The value is a String, Array<String> or Array<Term> which is interpreted according to the range of the associated property.

    Options Hash (options):

    • :type (String, Array<String,Term>) —

      Shortcut for rdf:type, values are interpreted as a Term.

    • :comment (String, Array<String>) —

      Shortcut for rdfs:comment, values are interpreted as a Literal.

    • :isDefinedBy (String, Array<String,Term>) —

      Shortcut for rdfs:isDefinedBy, values are interpreted as a Term.

    • :label (String, Array<String>) —

      Shortcut for rdfs:label, values are interpreted as a Literal.

    • :altLabel (String, Array<String>) —

      Shortcut for skos:altLabel, values are interpreted as a Literal.

    • :definition (String, Array<String>) —

      Shortcut for skos:definition, values are interpreted as a Literal.

    • :editorialNote (String, Array<String>) —

      Shortcut for skos:editorialNote, values are interpreted as a Literal.

    • :note (String, Array<String>) —

      Shortcut for skos:note, values are interpreted as a Literal.

    • :prefLabel (String, Array<String>) —

      Shortcut for skos:prefLabel, values are interpreted as a Literal.

    Returns:



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# File 'lib/rdf/vocabulary.rb', line 313

def ontology(*args)
  case args.length
  when 0
    @ontology if instance_variable_defined?(:@ontology)
  else
    uri, options = args
    URI.cache.delete(uri.to_s.to_sym)  # Clear any previous entry
    # Term attributes passed in a block for lazy evaluation. This helps to avoid load-time circular dependencies
    @ontology = Term.intern(uri.to_s, vocab: self, attributes: options || {})

    # If the URI is the same as the vocabulary namespace, also define it as a term
    props[:""] ||= @ontology if self.to_s == uri.to_s

    @ontology
  end
end

.properties ⇒ Object Also known as: __properties__

@return [Array<RDF::URI>] a list of properties in the current vocabulary



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# File 'lib/rdf/vocabulary.rb', line 333

def properties
  props.values
end

.property ⇒ RDF::Vocabulary::Term .property(name, options) ⇒ RDF::Vocabulary::Term Also known as: term, __property__

Overloads:

  • .property ⇒ RDF::Vocabulary::Term

    Returns property in the current vocabulary

    Returns:

  • .property(name, options) ⇒ RDF::Vocabulary::Term

    Defines a new property or class in the vocabulary as a Term.

    Examples:

    A simple term definition

    property :domain,
  comment: %(A domain of the subject property.),
  domain: "rdf:Property",
  label: "domain",
  range: "rdfs:Class",
  isDefinedBy: %(rdfs:),
  type: "rdf:Property"

    A term definition with tagged values

    property :actor,
comment: {en: "Subproperty of as:attributedTo that identifies the primary actor"},
domain: "https://www.w3.org/ns/activitystreams#Activity",
label: {en: "actor"},
range: term(
    type: "http://www.w3.org/2002/07/owl#Class",
    unionOf: list("https://www.w3.org/ns/activitystreams#Object", "https://www.w3.org/ns/activitystreams#Link")
  ),
subPropertyOf: "https://www.w3.org/ns/activitystreams#attributedTo",
type: "http://www.w3.org/2002/07/owl#ObjectProperty"

    A SKOS term with anonymous values

    term: :af,
  type: "jur:Country",
  isDefinedBy: "http://eulersharp.sourceforge.net/2003/03swap/countries#",
  "skos:exactMatch": [
    Term.new(
      type: "skos:Concept",
      inScheme: "iso3166-1-alpha-2",
      notation: "ax"),
    Term.new(
      type: "skos:Concept",
      inScheme: "iso3166-1-alpha-3",
      notation: "ala")
  ],
  "foaf:name": "Aland Islands"

    Parameters:

    • name (String, #to_s)
    • options (Hash{Symbol=>String,Array<String>}) —

      Any other values are expected to expands to a URI using built-in vocabulary prefixes. The value is a String, ‘HashSymbol=>String,Array<String>’ or Array<String,Hash{Symbol=>Array<String>}> which is interpreted according to the range of the associated property and by heuristically determining the value datatype. See attributes argument to #initialize.

    Returns:



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# File 'lib/rdf/vocabulary.rb', line 245

def property(*args)
  case args.length
  when 0
    Term.intern("#{self}property", vocab: self, attributes: {})
  else
    name = args.shift unless args.first.is_a?(Hash)
    options = args.last
    if name
      uri_str = [to_s, name.to_s].join('')
      URI.cache.delete(uri_str.to_sym)  # Clear any previous entry

      # Term attributes passed in a block for lazy evaluation. This helps to avoid load-time circular dependencies
      prop = Term.intern(uri_str, vocab: self, attributes: options || {})
      props[name.to_sym] = prop

      # If name is empty, also treat it as the ontology
      @ontology ||= prop if name.to_s.empty?

      # Define an accessor, except for problematic properties
      (class << self; self; end).send(:define_method, name) { prop } unless %w(property term hash).include?(name.to_s)
    else
      # Define the term without a name
      # Term attributes passed in a block for lazy evaluation. This helps to avoid load-time circular dependencies
      prop = Term.new(vocab: self, attributes: options)
    end
    prop
  end
end

.register(prefix, vocab, **params) ⇒ Hash

Register a vocabulary for internal prefix lookups. Parameters of interest include :uri, :class_name, :source, and :skip.

Parameters:

  • prefix (Symbol) —

    the prefix to use

  • vocab (String, Class) —

    either the URI or the vocab class

  • params (Hash{Symbol => String}) —

    Relevant parameters

Returns:

  • (Hash) —

    The parameter hash, but frozen

Raises:

  • (ArgumentError) 


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# File 'lib/rdf/vocabulary.rb', line 138

def register(prefix, vocab, **params)
  # check the input
  raise ArgumentError, "#{prefix} must be symbol-able" unless
    [String, Symbol].any? { |c| prefix.is_a? c }

  # note an explicit uri: param overrides
  case vocab
  when String then params[:uri] ||= vocab
  when Class
    raise ArgumentError, 'vocab must be an RDF::(Strict)Vocabulary' unless
      vocab.ancestors.include? RDF::Vocabulary
    params[:class] = vocab
    params[:uri] ||= vocab.to_uri.to_s
  end

  # fill in the class name
  params[:class_name] ||= prefix.to_s.upcase

  # now freeze and assign
  vocab_map[prefix.to_s.to_sym] = params.freeze
end

.strict? ⇒ Boolean

Is this a strict vocabulary, or a liberal vocabulary allowing arbitrary properties?

Returns:

  • (Boolean) 


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# File 'lib/rdf/vocabulary.rb', line 194

def strict?; false; end

.to_iri ⇒ RDF::URI

Returns the base URI for this vocabulary class. For IRI compatibility

Returns:



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# File 'lib/rdf/vocabulary.rb', line 446

def to_uri
  RDF::URI.intern(@@uris[self].to_s)
end

.to_s ⇒ String

Returns a string representation of this vocabulary class.

Returns:

  • (String) 


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# File 'lib/rdf/vocabulary.rb', line 481

def to_s
  @@uris.key?(self) ? @@uris[self].to_s : super
end

.to_uri ⇒ RDF::URI

Returns the base URI for this vocabulary class.

Returns:



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# File 'lib/rdf/vocabulary.rb', line 441

def to_uri
  RDF::URI.intern(@@uris[self].to_s)
end

.vocab_map ⇒ Hash{Symbol => Hash{Symbol => String}}

A hash of all vocabularies by prefix showing relevant URI and associated vocabulary Class Name

Returns:

  • (Hash{Symbol => Hash{Symbol => String}}) 


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# File 'lib/rdf/vocabulary.rb', line 114

def vocab_map
  # Create an initial duplicate of RDF::VOCABS. We want to
  # ensure the hash itself is modifiable but the values are
  # frozen.
  @vocab_map ||= RDF::VOCABS.transform_values(&:freeze)
end

Instance Method Details

#[](property) ⇒ URI

Returns the URI for the term property in this vocabulary.

Parameters:

Returns:



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# File 'lib/rdf/vocabulary.rb', line 685

def [](property)
  Term.intern([to_s, property.to_s].join(''), vocab: self, attributes: {})
end

#inspect ⇒ String

Returns a developer-friendly representation of this vocabulary.

Returns:

  • (String) 


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# File 'lib/rdf/vocabulary.rb', line 712

def inspect
  sprintf("#<%s:%#0x(%s)>", self.class.name, __id__, to_s)
end

#to_s ⇒ String

Returns a string representation of this vocabulary.

Returns:

  • (String) 


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# File 'lib/rdf/vocabulary.rb', line 704

def to_s
  @uri.to_s
end

#to_uri ⇒ URI Also known as: to_iri

Returns the base URI for this vocabulary.

Returns:



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# File 'lib/rdf/vocabulary.rb', line 693

def to_uri
  RDF::URI.intern(to_s)
end