add hash set type

Author: phpnode

src/index.js

@@ -7,6 +7,7 @@ import {make as makeStructType} from "./type-class/struct-type";
 import {make as makeObjectType} from "./type-class/object-type";
 import {make as makeArrayType} from "./type-class/array-type";
 import {make as makeHashMapType} from "./type-class/hash-map-type";
+import {make as makeHashSetType} from "./type-class/hash-set-type";
 
 import {make as makeStringPool} from "./string-pool";
 
@@ -41,6 +42,7 @@ export class Realm {
   ArrayType: Class<TypeClass<ArrayType<any>>>;
   StringType: Class<TypeClass<PrimitiveType<string>>>;
   HashMapType: Class<TypeClass<HashMapType<any, any>>>;
+  HashSetType: Class<TypeClass<HashSetType<any, any>>>;
 
   T: {
     [name: string|Symbol]: Type;
@@ -68,6 +70,7 @@ export class Realm {
     this.ArrayType = makeArrayType(this);
     this.StringType = makeStringType(this);
     this.HashMapType = makeHashMapType(this);
+    this.HashSetType = makeHashSetType(this);
     this.isInitialized = false;
   }
 

src/type-class/hash-set-type/README.md

@@ -0,0 +1,24 @@
+# HashSetType
+
+A type class for typed hash sets. Takes an element type as input and produces a hash set type which can store elements of that type.
+
+Usage:
+
+```js
+const {HashSetType, T} = realm;
+
+const StringSet = new HashSetType(T.String);
+
+const set = new StringSet();
+
+set.add('hello world');
+set.add('foo bar');
+
+set.has('hello world'); // true
+
+for (const entry of set) {
+  console.log(entry);
+}
+
+set.delete('foo bar');
+```