feat: add option for keeping variable type in output

src/render/emitter.ts

@@ -1,9 +1,18 @@
 export class Emitter {
-  public html = '';
+  public html: any = '';
   public break = false;
   public continue = false;
+  private keepOutputType? = false;
 
-  public write (html: string) {
-    this.html += html
+  constructor (keepOutputType: boolean|undefined) {
+    this.keepOutputType = keepOutputType
+  }
+
+  public write (html: any) {
+    if (this.keepOutputType && typeof html !== 'string') {
+      this.html = html
+    } else {
+      this.html += html as string
+    }
   }
 }