'use strict';
export default class Triple {
/**
* Represents a SPARQL triple (including object- and predicate-object-lists)
*
* @class Triple
* @constructor
* @param {String|Array} args - Either one (complete triple string) or three (separate subject, predicate, object) strings. Additionally, a string and an array can be supplied to create object- or predicate-object-lists.
*/
constructor(...args) {
var splitTriple = null;
switch (args.length) {
case 3:
let valid = true;
for (let arg of args) {
valid = typeof arg === 'string';
}
Eif (valid) splitTriple = args;
break;
case 2:
Eif (typeof args[0] === 'string' && Array.isArray(args[1])) {
let params = args[0].split(' ');
if (params.length === 2) {
// both subject and predicate were given
// we have an object list
splitTriple = [params[0], params[1], args[1]];
} else Eif (params.length === 1) {
// only subject was given
// this is an object-predicate list
splitTriple = [params[0], args[1], null];
}
}
break;
case 1:
Eif (typeof args[0] === 'string') {
splitTriple = args[0].split(' ');
}
break;
}
Eif (Array.isArray(splitTriple)) {
this.subject = splitTriple[0];
this.predicate = splitTriple[1];
this.object = splitTriple[2];
} else {
throw new Error('Triple: Wrong argument count or malformed input');
}
}
/**
* Retrieves the SPARQL string representation of the current instance
*
* @method toString
* @returns {String}
*/
toString() {
if (Array.isArray(this.predicate)) {
return `${this.subject} ${this.predicate.join(' ; ')}`;
} else if (Array.isArray(this.object)) {
return `${this.subject} ${this.predicate} ${this.object.join(' , ')}`;
}
return `${this.subject} ${this.predicate} ${this.object}`;
}
} |