Use branded types

TooTallNate · Dec 19, 2024 · 3a4fd9c · 3a4fd9c
1 parent b039a45
commit 3a4fd9c
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Showing 3 changed files with 12 additions and 6 deletions.
diff --git a/packages/ncm/src/content-meta-database.ts b/packages/ncm/src/content-meta-database.ts
@@ -85,7 +85,7 @@ export class NcmContentMetaDatabase {
 		inArr.set(new Uint8Array(key), 0x8);
 		const out = new ArrayBuffer(0x10);
 		this.#srv.dispatchInOut(3, inData, out);
-		return out;
+		return out as NcmContentId;
 	}
 
 	has(key: NcmContentMetaKey): boolean {

diff --git a/packages/ncm/src/content-storage.ts b/packages/ncm/src/content-storage.ts
@@ -33,7 +33,7 @@ export class NcmContentStorage {
 		//}
 		const uuid = new ArrayBuffer(0x10);
 		this.#srv.dispatchOut(0, uuid);
-		return uuid;
+		return uuid as NcmPlaceHolderId;
 	}
 
 	createPlaceHolder(
@@ -223,7 +223,7 @@ export class NcmContentStorage {
 		const outCount = out[0];
 		const rtn: NcmPlaceHolderId[] = new Array(outCount);
 		for (let i = 0; i < outCount; i++) {
-			rtn[i] = outIds.slice(i * 0x10, i * 0x10 + 0x10);
+			rtn[i] = outIds.slice(i * 0x10, i * 0x10 + 0x10) as NcmPlaceHolderId;
 		}
 		return rtn;
 	}
@@ -257,7 +257,7 @@ export class NcmContentStorage {
 		const outCount = out[0];
 		const rtn: NcmContentId[] = new Array(outCount);
 		for (let i = 0; i < outCount; i++) {
-			rtn[i] = outIds.slice(i * 0x10, i * 0x10 + 0x10);
+			rtn[i] = outIds.slice(i * 0x10, i * 0x10 + 0x10) as NcmContentId;
 		}
 		return rtn;
 	}

diff --git a/packages/ncm/src/types.ts b/packages/ncm/src/types.ts
@@ -60,13 +60,19 @@ export enum NcmContentMetaPlatform {
 //typedef struct {
 //    u8 c[0x10]; ///< Id
 //} NcmContentId;
-export type NcmContentId = ArrayBuffer;
+declare const contentIdSymbol: unique symbol;
+export type NcmContentId = ArrayBuffer & {
+	[contentIdSymbol]: void;
+};
 
 /// PlaceHolderId
 //typedef struct {
 //    Uuid uuid;  ///< UUID
 //} NcmPlaceHolderId;
-export type NcmPlaceHolderId = ArrayBuffer;
+declare const placeHolderIdSymbol: unique symbol;
+export type NcmPlaceHolderId = ArrayBuffer & {
+	[placeHolderIdSymbol]: void;
+};
 
 /// ContentMetaKey
 //typedef struct {