rename AbstractRef to AbstractStructRef

src/structs/AbstractItem.js

@@ -5,7 +5,7 @@ import {
   writeID,
   GC,
   nextID,
-  AbstractRef,
+  AbstractStructRef,
   AbstractStruct,
   replaceStruct,
   addStruct,
@@ -487,7 +487,7 @@ export class AbstractItem extends AbstractStruct {
   }
 }
 
-export class AbstractItemRef extends AbstractRef {
+export class AbstractItemRef extends AbstractStructRef {
   /**
    * @param {decoding.Decoder} decoder
    * @param {ID} id

src/structs/AbstractStruct.js

@@ -53,7 +53,7 @@ export class AbstractStruct {
   }
 }
 
-export class AbstractRef {
+export class AbstractStructRef {
   /**
    * @param {ID} id
    */

src/structs/GC.js

@@ -2,7 +2,7 @@
  * @module structs
  */
 import {
-  AbstractRef,
+  AbstractStructRef,
   AbstractStruct,
   createID,
   addStruct,
@@ -60,7 +60,7 @@ export class GC extends AbstractStruct {
   }
 }
 
-export class GCRef extends AbstractRef {
+export class GCRef extends AbstractStructRef {
   /**
    * @param {decoding.Decoder} decoder
    * @param {ID} id