diff --git a/src/common/extension-state.ts b/src/common/extension-state.ts
new file mode 100644
index 0000000..c4fb213
--- /dev/null
+++ b/src/common/extension-state.ts
@@ -0,0 +1,17 @@
+import { ExtensionContext, Memento } from "vscode";
+
+export class ExtensionState {
+    private static _context: ExtensionContext;
+
+    static get global(): Memento {
+        return this._context.globalState;
+    }
+
+    static get workspace(): Memento {
+        return this._context.workspaceState;
+    }
+
+    static configure(context: ExtensionContext): void {
+        this._context = context;
+    }
+}
diff --git a/src/common/index.ts b/src/common/index.ts
index 6a9e980..b322d14 100644
--- a/src/common/index.ts
+++ b/src/common/index.ts
@@ -1 +1,2 @@
 export * from "./create-document-selector";
+export * from "./extension-state";
diff --git a/src/extension.ts b/src/extension.ts
index 265594f..2cad6cf 100644
--- a/src/extension.ts
+++ b/src/extension.ts
@@ -3,7 +3,7 @@ import {
     TextEditor, TextEditorSelectionChangeEvent, TextEditorSelectionChangeKind
     } from "vscode";
 
-import { createDocumentSelector } from "./common";
+import { createDocumentSelector, ExtensionState } from "./common";
 import { XQueryCompletionItemProvider } from "./completion";
 import { XmlFormatterFactory, XmlFormattingEditProvider } from "./formatting";
 import { formatAsXml, minifyXml } from "./formatting/commands";
@@ -14,11 +14,8 @@ import { executeXQuery } from "./xquery-execution/commands";
 
 import * as constants from "./constants";
 
-export const ExtensionState: { global?: Memento, workspace?: Memento } = { };
-
 export function activate(context: ExtensionContext) {
-    ExtensionState.global = context.globalState;
-    ExtensionState.workspace = context.workspaceState;
+    ExtensionState.configure(context);
 
     const config = workspace.getConfiguration(constants.extensionPrefix);
 
diff --git a/src/xpath/commands/evaluateXPath.ts b/src/xpath/commands/evaluateXPath.ts
index 8f78a11..a22d10a 100644
--- a/src/xpath/commands/evaluateXPath.ts
+++ b/src/xpath/commands/evaluateXPath.ts
@@ -1,8 +1,8 @@
 import { window, workspace } from "vscode";
 import { TextEditor, TextEditorEdit, ViewColumn } from "vscode";
 
+import { ExtensionState } from "../../common";
 import * as constants from "../../constants";
-import { ExtensionState } from "../../extension";
 
 import { EvaluatorResult, EvaluatorResultType, XPathEvaluator } from "../xpath-evaluator";