extensions.rb in sxp-1.2.0

- old
+ new
@@ -1,26 +1,326 @@
+# -*- encoding: utf-8 -*-
+require 'bigdecimal'
+require 'matrix'
+require 'time'
+
 ##
+# Extensions for Ruby's `Object` class.
+class Object
+  ##
+  # Returns the SXP representation of this object.
+  #
+  # @return [String]
+  def to_sxp(**options)
+    to_s.to_json
+  end
+end
+
+##
+# Extensions for Ruby's `NilClass` class.
+class NilClass
+  ##
+  # Returns the SXP representation of this object.
+  #
+  # @return [String]
+  def to_sxp(**options)
+    '#n'
+  end
+end
+
+##
+# Extensions for Ruby's `FalseClass` class.
+class FalseClass
+  ##
+  # Returns the SXP representation of this object.
+  #
+  # @return [String]
+  def to_sxp(**options)
+    '#f'
+  end
+end
+
+##
+# Extensions for Ruby's `TrueClass` class.
+class TrueClass
+  ##
+  # Returns the SXP representation of this object.
+  #
+  # @return [String]
+  def to_sxp(**options)
+    '#t'
+  end
+end
+
+##
+# Extensions for Ruby's `String` class.
+class String
+  ##
+  # Returns the SXP representation of this object.
+  #
+  # @return [String]
+  def to_sxp(**options)
+    inspect
+  end
+end
+
+##
 # Extensions for Ruby's `Symbol` class.
 class Symbol
   ##
+  # Returns the SXP representation of this object.
+  #
+  # @return [String]
+  def to_sxp(**options)
+    to_s
+  end
+
+  ##
   # Returns `true` if this is a keyword symbol.
   #
   # @return [Boolean]
   def keyword?
     to_s[-1] == ?:
   end
 end
 
-# Update RDF::URI if RDF is loaded
+##
+# Extensions for Ruby's `Integer` class.
+class Integer
+  ##
+  # Returns the SXP representation of this object.
+  #
+  # @return [String]
+  def to_sxp(**options)
+    to_s
+  end
+end
+
+##
+# Extensions for Ruby's `BigDecimal` class.
+class BigDecimal
+  ##
+  # Returns the SXP representation of this object.
+  #
+  # @return [String]
+  def to_sxp(**options)
+    to_f.to_s
+  end
+end
+
+##
+# Extensions for Ruby's `Float` class.
+class Float
+  ##
+  # Returns the SXP representation of this object.
+  #
+  # @return [String]
+  def to_sxp(**options)
+    case
+      when nan? then 'nan.0'
+      when infinite? then (infinite? > 0 ? '+inf.0' : '-inf.0')
+      else to_s
+    end
+  end
+end
+
+##
+# Extensions for Ruby's `Array` class.
+class Array
+  ##
+  # Returns the SXP representation of this object.
+  #
+  # @return [String]
+  def to_sxp()
+    '(' << map { |x| x.to_sxp(**options) }.join(' ') << ')'
+  end
+end
+
+##
+# Extensions for Ruby's `Vector` class.
+class Vector
+  ##
+  # Returns the SXP representation of this object.
+  #
+  # @return [String]
+  def to_sxp(**options)
+    '#(' << to_a.map { |x| x.to_sxp(**options) }.join(' ') << ')'
+  end
+end
+
+##
+# Extensions for Ruby's `Hash` class.
+class Hash
+  ##
+  # Returns the SXP representation of this object.
+  #
+  # @return [String]
+  def to_sxp(**options)
+    to_a.to_sxp(**options)
+  end
+end
+
+##
+# Extensions for Ruby's `Time` class.
+class Time
+  ##
+  # Returns the SXP representation of this object.
+  #
+  # @return [String]
+  def to_sxp(**options)
+    '#@' << (respond_to?(:xmlschema) ? xmlschema : to_i).to_s
+  end
+end
+
+##
+# Extensions for Ruby's `Regexp` class.
+class Regexp
+  ##
+  # Returns the SXP representation of this object.
+  #
+  # @return [String]
+  def to_sxp(**options)
+    '#' << inspect
+  end
+end
+
 begin
-  require 'rdf'
+  require 'rdf' # For SPARQL/RDF
 
   ##
-  # Extensions for RDF::URI
+  # Extensions for Ruby's `Array` class.
+  # These extensions depend on RDF being loaded
+  class Array
+    ##
+    # Returns the SXP representation of this object.
+    #
+    # If array is of the form `[:base, uri, ..]`, the base_uri is taken from the second value
+    #
+    # If array is of the form `[:prefix, [..], ..]`, prefixes are taken from the second value
+    #
+    # Prefixes always are terminated by a ':'
+    #
+    # @param [Hash{Symbol => RDF::URI}] prefixes(nil)
+    # @param [RDF::URI] base_uri(nil)
+    # @return [String]
+    def to_sxp(prefixes: nil, base_uri: nil, **options)
+      if self.first == :base && self.length == 3 && self[1].is_a?(RDF::URI)
+        base_uri = self[1]
+        '(' << (
+        self[0,2].map(&:to_sxp) <<
+          self.last.to_sxp(prefixes: prefixes, base_uri: base_uri, **options)
+        ).join(' ') << ')'
+      elsif self.first == :prefix && self.length == 3 && self[1].is_a?(Array)
+        prefixes = prefixes ? prefixes.dup : {}
+        self[1].each do |defn|
+          prefixes[defn.first.to_s.chomp(':').to_sym] = RDF::URI(defn.last) if
+            defn.is_a?(Array) && defn.length == 2
+        end
+        pfx_sxp = self[1].map {|(p,s)|["#{p.to_s.chomp(':')}:".to_sym, RDF::URI(s)]}.to_sxp
+        '(' << [
+          :prefix,
+          pfx_sxp,
+          self.last.to_sxp(prefixes: prefixes, base_uri: base_uri, **options)
+        ].join(' ') << ')'
+      else
+        '(' << map { |x| x.to_sxp(prefixes: prefixes, base_uri: base_uri, **options) }.join(' ') << ')'
+      end
+    end
+  end
+
   class RDF::URI
+    ##
+    # Returns the SXP representation of this a URI. Uses Lexical representation, if set, otherwise, any PName match, otherwise, the relativized version of the URI if a base_uri is given, otherwise just the URI.
+    #
+    # @param [Hash{Symbol => RDF::URI}] prefixes(nil)
+    # @param [RDF::URI] base_uri(nil)
+    # @return [String]
+    def to_sxp(prefixes: nil, base_uri: nil, **options)
+      return lexical if lexical
+      pn = pname(prefixes: prefixes || {})
+      return pn unless to_s == pn
+      md = self == base_uri ? '' : self.relativize(base_uri)
+      "<#{md}>"
+    end
+
     # Original lexical value of this URI to allow for round-trip serialization.
     def lexical=(value); @lexical = value; end
     def lexical; @lexical; end
   end
+
+  class RDF::Node
+    ##
+    # Returns the SXP representation of this object.
+    #
+    # @return [String]
+    def to_sxp(**options)
+      to_s
+    end
+  end
+
+  class RDF::Literal
+    ##
+    # Returns the SXP representation of a Literal.
+    #
+    # @return [String]
+    def to_sxp(**options)
+      case datatype
+      when RDF::XSD.boolean, RDF::XSD.integer, RDF::XSD.double, RDF::XSD.decimal, RDF::XSD.time
+        # Retain stated lexical form if possible
+        valid? ? to_s : object.to_sxp(**options)
+      else
+        text = value.dump
+        text << "@#{language}" if self.has_language?
+        text << "^^#{datatype.to_sxp(**options)}" if self.has_datatype?
+        text
+      end
+    end
+
+    class Double
+      ##
+      # Returns the SXP representation of this object.
+      #
+      # @return [String]
+      def to_sxp(**options)
+        case
+          when nan? then 'nan.0'
+          when infinite? then (infinite? > 0 ? '+inf.0' : '-inf.0')
+          else canonicalize.to_s.downcase
+        end
+      end
+    end
+  end
+
+  class RDF::Query
+    # Transform Query into an Array form of an SXP
+    #
+    # If Query is named, it's treated as a GroupGraphPattern, otherwise, a BGP
+    #
+    # @return [Array]
+    def to_sxp(**options)
+      res = [:bgp] + patterns
+      (named? ? [:graph, graph_name, res] : res).to_sxp(**options)
+    end
+  end
+
+  class RDF::Query::Pattern
+    # Transform Query Pattern into an SXP
+    #
+    # @return [String]
+    def to_sxp(**options)
+      [:triple, subject, predicate, object].to_sxp(**options)
+    end
+  end
+
+  class RDF::Query::Variable
+    ##
+    # Transform Query variable into an SXP.
+    #
+    # @return [String]
+    def to_sxp(**options)
+      prefix = distinguished? ? (existential? ? '$' : '?') : (existential? ? '$$' : '??')
+      unbound? ? "#{prefix}#{name}".to_sym.to_sxp : ["#{prefix}#{name}".to_sym, value].to_sxp
+    end
+  end
 rescue LoadError
-  # Ignore
+  # Ignore if RDF not loaded
 end