fix: #2206 indexing regexp

src/common.ts

@@ -207,6 +207,7 @@ export namespace CommonNames {
   export const I31ref = "I31ref";
   export const Dataref = "Dataref";
   export const String = "String";
+  export const RegExp = "RegExp";
   export const Object = "Object";
   export const Array = "Array";
   export const StaticArray = "StaticArray";

src/program.ts

@@ -634,6 +634,14 @@ export class Program extends DiagnosticEmitter {
   }
   private _stringInstance: Class | null = null;
 
+  /** Gets the standard `RegExp` instance. */
+  get regexpInstance(): Class {
+    var cached = this._regexpInstance;
+    if (!cached) this._regexpInstance = cached = this.requireClass(CommonNames.RegExp);
+    return cached;
+  }
+  private _regexpInstance: Class | null = null;
+
   /** Gets the standard `Object` instance. */
   get objectInstance(): Class {
     var cached = this._objectInstance;

src/resolver.ts

@@ -2191,6 +2191,9 @@ export class Resolver extends DiagnosticEmitter {
       case LiteralKind.TEMPLATE: {
         return this.program.stringInstance;
       }
+      case LiteralKind.REGEXP: {
+        return this.program.regexpInstance;
+      }
       case LiteralKind.ARRAY: {
         let classReference = ctxType.getClass();
         if (classReference && classReference.prototype == this.program.arrayPrototype) {

tests/compiler/indexing-regexp.json

@@ -0,0 +1,7 @@
+{
+  "asc_flags": [
+  ],
+  "stderr": [
+    "TS2329: Index signature is missing in type '~lib/regexp/RegExp'"
+  ]
+}

tests/compiler/indexing-regexp.ts

@@ -0,0 +1 @@
+/ /[0];

tests/compiler/typeof-regexp.json

@@ -0,0 +1,7 @@
+{
+  "asc_flags": [
+  ],
+  "stderr": [
+    "AS100: Not implemented: Regular expressions"
+  ]
+}

tests/compiler/typeof-regexp.ts

@@ -0,0 +1 @@
+typeof / /;