Export RDF/JS Term and Quad constructors.

Author: RubenVerborgh

src/N3DataFactory.js

@@ -4,12 +4,23 @@
 import namespaces from './IRIs';
 const { rdf, xsd } = namespaces;
 
-var DataFactory, DEFAULTGRAPH;
+let DEFAULTGRAPH;
+let _blankNodeCounter = 0;
 
-var _blankNodeCounter = 0;
+// ## DataFactory singleton
+const DataFactory = {
+  namedNode,
+  blankNode,
+  variable,
+  literal,
+  defaultGraph,
+  quad,
+  triple: quad,
+};
+export default DataFactory;
 
 // ## Term constructor
-class Term {
+export class Term {
   constructor(id) {
     this.id = id;
   }
@@ -41,15 +52,15 @@ class Term {
 
 
 // ## NamedNode constructor
-class NamedNode extends Term {
+export class NamedNode extends Term {
   // ### The term type of this term
   get termType() {
     return 'NamedNode';
   }
 }
 
 // ## Literal constructor
-class Literal extends Term {
+export class Literal extends Term {
   // ### The term type of this term
   get termType() {
     return 'Literal';
@@ -108,7 +119,7 @@ class Literal extends Term {
 }
 
 // ## BlankNode constructor
-class BlankNode extends Term {
+export class BlankNode extends Term {
   constructor(name) {
     super('_:' + name);
   }
@@ -124,7 +135,7 @@ class BlankNode extends Term {
   }
 }
 
-class Variable extends Term {
+export class Variable extends Term {
   constructor(name) {
     super('?' + name);
   }
@@ -141,7 +152,7 @@ class Variable extends Term {
 }
 
 // ## DefaultGraph constructor
-class DefaultGraph extends Term {
+export class DefaultGraph extends Term {
   constructor() {
     super('');
     return DEFAULTGRAPH || this;
@@ -166,7 +177,7 @@ DEFAULTGRAPH = new DefaultGraph();
 
 
 // ### Constructs a term from the given internal string ID
-function fromId(id, factory) {
+export function termFromId(id, factory) {
   factory = factory || DataFactory;
 
   // Falsy value or empty string indicate the default graph
@@ -194,7 +205,7 @@ function fromId(id, factory) {
 }
 
 // ### Constructs an internal string ID from the given term or ID string
-function toId(term) {
+export function termToId(term) {
   if (typeof term === 'string')
     return term;
   if (term instanceof Term)
@@ -217,7 +228,7 @@ function toId(term) {
 
 
 // ## Quad constructor
-class Quad {
+export class Quad {
   constructor(subject, predicate, object, graph) {
     this.subject   = subject;
     this.predicate = predicate;
@@ -243,35 +254,9 @@ class Quad {
                       this.graph.equals(other.graph);
   }
 }
+export { Quad as Triple };
 
 
-// ## DataFactory singleton
-DataFactory = {
-  // ### Public factory functions
-  namedNode,
-  blankNode,
-  variable,
-  literal,
-  defaultGraph,
-  quad,
-  triple: quad,
-
-  // ### Internal datatype constructors
-  internal: {
-    Term,
-    NamedNode,
-    BlankNode,
-    Variable,
-    Literal,
-    DefaultGraph,
-    Quad,
-    Triple: Quad,
-    fromId,
-    toId,
-  },
-};
-export default DataFactory;
-
 // ### Creates an IRI
 function namedNode(iri) {
   return new NamedNode(iri);

src/N3Store.js

@@ -1,10 +1,8 @@
 // **N3Store** objects store N3 quads by graph in memory.
-import N3DataFactory from './N3DataFactory';
+import { default as N3DataFactory, termToId, termFromId } from './N3DataFactory';
 import { Readable } from 'stream';
 import namespaces from './IRIs';
 
-const { toId, fromId } = N3DataFactory.internal;
-
 // ## Constructor
 export default class N3Store {
   constructor(quads, options) {
@@ -111,11 +109,11 @@ export default class N3Store {
             // Create quads for all items found in index 2.
             for (var l = 0; l < values.length; l++) {
               var parts = { subject: null, predicate: null, object: null };
-              parts[name0] = fromId(entity0, this._factory);
-              parts[name1] = fromId(entity1, this._factory);
-              parts[name2] = fromId(entityKeys[values[l]], this._factory);
+              parts[name0] = termFromId(entity0, this._factory);
+              parts[name1] = termFromId(entity1, this._factory);
+              parts[name2] = termFromId(entityKeys[values[l]], this._factory);
               var quad = this._factory.quad(
-                parts.subject, parts.predicate, parts.object, fromId(graph, this._factory));
+                parts.subject, parts.predicate, parts.object, termFromId(graph, this._factory));
               if (array)
                 array.push(quad);
               else if (callback(quad))
@@ -204,7 +202,7 @@ export default class N3Store {
     return function (id) {
       if (!(id in uniqueIds)) {
         uniqueIds[id] = true;
-        callback(fromId(entities[id]));
+        callback(termFromId(entities[id]));
       }
     };
   }
@@ -220,10 +218,10 @@ export default class N3Store {
         predicate = subject.predicate, subject = subject.subject;
 
     // Convert terms to internal string representation
-    subject = toId(subject);
-    predicate = toId(predicate);
-    object = toId(object);
-    graph = toId(graph);
+    subject = termToId(subject);
+    predicate = termToId(predicate);
+    object = termToId(object);
+    graph = termToId(graph);
 
     // Find the graph that will contain the triple
     var graphItem = this._graphs[graph];
@@ -274,10 +272,10 @@ export default class N3Store {
         predicate = subject.predicate, subject = subject.subject;
 
     // Convert terms to internal string representation
-    subject = toId(subject);
-    predicate = toId(predicate);
-    object = toId(object);
-    graph = toId(graph);
+    subject = termToId(subject);
+    predicate = termToId(predicate);
+    object = termToId(object);
+    graph = termToId(graph);
 
     // Find internal identifiers for all components
     // and verify the quad exists.
@@ -329,10 +327,10 @@ export default class N3Store {
   // Setting any field to `undefined` or `null` indicates a wildcard.
   getQuads(subject, predicate, object, graph) {
     // Convert terms to internal string representation
-    subject = subject && toId(subject);
-    predicate = predicate && toId(predicate);
-    object = object && toId(object);
-    graph = graph && toId(graph);
+    subject = subject && termToId(subject);
+    predicate = predicate && termToId(predicate);
+    object = object && termToId(object);
+    graph = graph && termToId(graph);
 
     var quads = [], graphs = this._getGraphs(graph), content,
         ids = this._ids, subjectId, predicateId, objectId;
@@ -393,10 +391,10 @@ export default class N3Store {
   // Setting any field to `undefined` or `null` indicates a wildcard.
   countQuads(subject, predicate, object, graph) {
     // Convert terms to internal string representation
-    subject = subject && toId(subject);
-    predicate = predicate && toId(predicate);
-    object = object && toId(object);
-    graph = graph && toId(graph);
+    subject = subject && termToId(subject);
+    predicate = predicate && termToId(predicate);
+    object = object && termToId(object);
+    graph = graph && termToId(graph);
 
     var count = 0, graphs = this._getGraphs(graph), content,
         ids = this._ids, subjectId, predicateId, objectId;
@@ -458,10 +456,10 @@ export default class N3Store {
   // Setting any field to `undefined` or `null` indicates a wildcard.
   some(callback, subject, predicate, object, graph) {
     // Convert terms to internal string representation
-    subject = subject && toId(subject);
-    predicate = predicate && toId(predicate);
-    object = object && toId(object);
-    graph = graph && toId(graph);
+    subject = subject && termToId(subject);
+    predicate = predicate && termToId(predicate);
+    object = object && termToId(object);
+    graph = graph && termToId(graph);
 
     var graphs = this._getGraphs(graph), content,
         ids = this._ids, subjectId, predicateId, objectId;
@@ -526,9 +524,9 @@ export default class N3Store {
   // Setting any field to `undefined` or `null` indicates a wildcard.
   forSubjects(callback, predicate, object, graph) {
     // Convert terms to internal string representation
-    predicate = predicate && toId(predicate);
-    object = object && toId(object);
-    graph = graph && toId(graph);
+    predicate = predicate && termToId(predicate);
+    object = object && termToId(object);
+    graph = graph && termToId(graph);
 
     var ids = this._ids, graphs = this._getGraphs(graph), content, predicateId, objectId;
     callback = this._uniqueEntities(callback);
@@ -572,9 +570,9 @@ export default class N3Store {
   // Setting any field to `undefined` or `null` indicates a wildcard.
   forPredicates(callback, subject, object, graph) {
     // Convert terms to internal string representation
-    subject = subject && toId(subject);
-    object = object && toId(object);
-    graph = graph && toId(graph);
+    subject = subject && termToId(subject);
+    object = object && termToId(object);
+    graph = graph && termToId(graph);
 
     var ids = this._ids, graphs = this._getGraphs(graph), content, subjectId, objectId;
     callback = this._uniqueEntities(callback);
@@ -618,9 +616,9 @@ export default class N3Store {
   // Setting any field to `undefined` or `null` indicates a wildcard.
   forObjects(callback, subject, predicate, graph) {
     // Convert terms to internal string representation
-    subject = subject && toId(subject);
-    predicate = predicate && toId(predicate);
-    graph = graph && toId(graph);
+    subject = subject && termToId(subject);
+    predicate = predicate && termToId(predicate);
+    graph = graph && termToId(graph);
 
     var ids = this._ids, graphs = this._getGraphs(graph), content, subjectId, predicateId;
     callback = this._uniqueEntities(callback);

src/N3Writer.js

@@ -1,6 +1,6 @@
 // **N3Writer** writes N3 documents.
 import namespaces from './IRIs';
-import N3DataFactory from './N3DataFactory';
+import { default as N3DataFactory, Term } from './N3DataFactory';
 
 const DEFAULTGRAPH = N3DataFactory.defaultGraph();
 
@@ -15,7 +15,7 @@ var escape    = /["\\\t\n\r\b\f\u0000-\u0019\ud800-\udbff]/,
     };
 
 // ## Placeholder class to represent already pretty-printed terms
-class SerializedTerm extends N3DataFactory.internal.Term {
+class SerializedTerm extends Term {
   // Pretty-printed nodes are not equal to any other node
   // (e.g., [] does not equal [])
   equals() {

src/index.js

@@ -1,4 +1,3 @@
-import DataFactory from './N3DataFactory';
 import Lexer from './N3Lexer';
 import Parser from './N3Parser';
 import Writer from './N3Writer';
@@ -7,13 +6,42 @@ import StreamParser from './N3StreamParser';
 import StreamWriter from './N3StreamWriter';
 import * as Util from './N3Util';
 
+import {
+  default as DataFactory,
+
+  Term,
+  NamedNode,
+  Literal,
+  BlankNode,
+  Variable,
+  DefaultGraph,
+  Quad,
+  Triple,
+
+  termFromId,
+  termToId,
+} from './N3DataFactory';
+
 export {
-  DataFactory,
   Lexer,
   Parser,
   Writer,
   Store,
   StreamParser,
   StreamWriter,
   Util,
+
+  DataFactory,
+
+  Term,
+  NamedNode,
+  Literal,
+  BlankNode,
+  Variable,
+  DefaultGraph,
+  Quad,
+  Triple,
+
+  termFromId,
+  termToId,
 };

test/BlankNode-test.js

@@ -1,6 +1,4 @@
-import { DataFactory } from '../src/';
-
-const { BlankNode, Term } = DataFactory.internal;
+import { BlankNode, Term } from '../src/';
 
 describe('BlankNode', function () {
   describe('The BlankNode module', function () {

test/DefaultGraph-test.js

@@ -1,6 +1,4 @@
-import { DataFactory } from '../src/';
-
-const { DefaultGraph, Term } = DataFactory.internal;
+import { DefaultGraph, Term } from '../src/';
 
 describe('DefaultGraph', function () {
   describe('The DefaultGraph module', function () {

test/Literal-test.js

@@ -1,6 +1,4 @@
-import { DataFactory } from '../src/';
-
-const { Literal, NamedNode, Term } = DataFactory.internal;
+import { Literal, NamedNode, Term } from '../src/';
 
 describe('Literal', function () {
   describe('The Literal module', function () {

test/N3DataFactory-test.js

@@ -1,6 +1,12 @@
-import { DataFactory } from '../src/';
-
-const { NamedNode, Literal, BlankNode, Variable, DefaultGraph, Quad } = DataFactory.internal;
+import {
+  DataFactory,
+  NamedNode,
+  Literal,
+  BlankNode,
+  Variable,
+  DefaultGraph,
+  Quad,
+} from '../src/';
 
 describe('DataFactory', function () {
   describe('namedNode', function () {