fix: widen mode option type in ndarray/sub2ind to accept a single mode

PR-URL: #12628
Co-authored-by: Athan Reines <kgryte@gmail.com>
Reviewed-by: Athan Reines <kgryte@gmail.com> 
Signed-off-by: Athan Reines <kgryte@gmail.com>

Author: Planeshifter

lib/node_modules/@stdlib/ndarray/sub2ind/docs/types/index.d.ts

@@ -19,10 +19,9 @@
 // TypeScript Version: 4.1
 
 /// <reference types="@stdlib/types"/>
-/// <reference types="node"/>
 
 import { ArrayLike } from '@stdlib/types/array';
-import { Order } from '@stdlib/types/ndarray';
+import { Mode, Order } from '@stdlib/types/ndarray';
 
 /**
 * Interface defining function options.
@@ -31,10 +30,10 @@ interface Options {
 	/**
 	* Specifies how to handle subscripts which exceed array dimensions (default: ['throw']).
 	*/
-	mode?: Array<string>;
+	mode?: Mode | Array<Mode>;
 
 	/**
-	* specifies whether an array is row-major (C-style) or column-major (Fortran-style) (default: 'row-major').
+	* Specifies whether an array is row-major (C-style) or column-major (Fortran-style) (default: 'row-major').
 	*/
 	order?: Order;
 }
@@ -57,9 +56,10 @@ interface Options {
 * @param args - subscripts followed by an optional options object
 * @throws first argument must be an array-like object containing nonnegative integers
 * @throws subscripts must be integer valued
+* @throws options argument must be an object
 * @throws must provide valid options
 * @throws must provide subscripts which do not exceed array dimensions
-* @throws number of subscripts much match the number of dimensions
+* @throws number of subscripts must match the number of dimensions
 * @returns linear index
 *
 * @example

lib/node_modules/@stdlib/ndarray/sub2ind/docs/types/test.ts

@@ -24,6 +24,7 @@ import subd2ind = require( './index' );
 // The function returns a number...
 {
 	const shape = [ 3, 3, 3 ];
+	subd2ind( shape, 1, 2, 2, { 'mode': 'throw' } ); // $ExpectType number
 	subd2ind( shape, 1, 2, 2, { 'mode': [ 'throw' ] } ); // $ExpectType number
 	subd2ind( shape, 1, 2, 2, { 'order': 'row-major' } ); // $ExpectType number
 }
@@ -65,7 +66,7 @@ import subd2ind = require( './index' );
 	subd2ind( shape, 1, 2, 2, { 'order': ( x: number ): number => x } ); // $ExpectError
 }
 
-// The compiler throws an error if the function is provided a `mode` option which is not an array of strings...
+// The compiler throws an error if the function is provided a `mode` option which is not a recognized mode or array of recognized modes...
 {
 	const shape = [ 3, 3, 3 ];
 	subd2ind( shape, 1, 2, 2, { 'mode': 'abc' } ); // $ExpectError