refactor: update packageName

Author: velut

src/errors.ts

@@ -21,3 +21,9 @@ export class ProjectError extends Data.TaggedError("ProjectError")<{ readonly ca
 export class PackageDeclarationsError extends Data.TaggedError("PackageDeclarationsError")<{
 	cause?: unknown;
 }> {}
+
+/** `PackageNameError` occurs when the name of a package is not a name valid on the npm registry. */
+export class PackageNameError extends Data.TaggedError("PackageNameError")<{
+	warnings?: string[];
+	errors?: string[];
+}> {}

src/package-name.ts

@@ -1,20 +1,17 @@
-import { Data, Effect } from "effect";
+import { Effect } from "effect";
 import validate from "validate-npm-package-name";
+import { PackageNameError } from "./errors.ts";
 
-/** @internal */
-export class PackageNameError extends Data.TaggedError("PackageNameError")<{
-	warnings?: string[];
-	errors?: string[];
-}> {}
-
-/** @internal */
-export const packageName = (pkg: string) =>
-	Effect.gen(function* () {
+/**
+`packageName` returns an Effect for validating package names
+according to the npm registry's new naming rules.
+*/
+export function packageName(pkg: string) {
+	return Effect.gen(function* () {
 		const versionMarker = pkg.lastIndexOf("@");
 		const pkgName = pkg.slice(0, versionMarker > 0 ? versionMarker : undefined);
 		const { validForNewPackages, warnings, errors } = validate(pkgName);
-		if (!validForNewPackages) {
-			return yield* new PackageNameError({ warnings, errors });
-		}
+		if (!validForNewPackages) return yield* new PackageNameError({ warnings, errors });
 		return pkgName;
 	});
+}