Add internal set library

Author: ry

lib/_set.js

@@ -0,0 +1,29 @@
+var L = require('_linklist');
+function Set() {
+  this.list = {};
+  L.init(this.list);
+}
+exports.Set = Set;
+
+
+exports.create = function() {
+  return new Set();
+};
+
+
+Set.prototype.add = function(obj) {
+  L.init(obj);
+  L.append(this.list, obj);
+  obj.__setMembership = this;
+};
+
+
+Set.prototype.remove = function(obj) {
+  L.remove(obj);
+  obj.__setMembership = null;
+};
+
+
+Set.prototype.contains = function(obj) {
+  return obj.__setMembership === this;
+};

test/simple/test-set.js

@@ -0,0 +1,35 @@
+var common = require('../common');
+var set = require('_set');
+var assert = require('assert');
+
+
+var s = set.create();
+
+var A = { name: "A" };
+var B = { name: "B" };
+var C = { name: "C" };
+var D = { name: "D" };
+
+
+s.add(A);
+
+assert.ok(s.contains(A));
+assert.ok(!s.contains(B));
+assert.ok(!s.contains(C));
+assert.ok(!s.contains(D));
+
+s.remove(A);
+
+assert.ok(!s.contains(A));
+assert.ok(!s.contains(B));
+assert.ok(!s.contains(C));
+assert.ok(!s.contains(D));
+
+s.add(A);
+s.add(B);
+
+
+assert.ok(s.contains(A));
+assert.ok(s.contains(B));
+assert.ok(!s.contains(C));
+assert.ok(!s.contains(D));