suggestion: add overload for "solo selector" without input selectors

src/createSelectorCreator.ts

@@ -141,6 +141,32 @@ export interface CreateSelectorFunction<
     OverrideArgsMemoizeFunction
   > &
     InterruptRecursion
+
+    <
+    SoloSelector extends (...args: any[]) => any,
+    OverrideMemoizeFunction extends UnknownMemoizer = MemoizeFunction,
+    OverrideArgsMemoizeFunction extends UnknownMemoizer = ArgsMemoizeFunction
+  >(
+    selector: SoloSelector,
+    createSelectorOptions?: Simplify<
+      CreateSelectorOptions<
+        MemoizeFunction,
+        ArgsMemoizeFunction,
+        OverrideMemoizeFunction,
+        OverrideArgsMemoizeFunction
+      >
+    >
+  ): OutputSelector<
+    ParametersToVirtualInputSelectors<Parameters<SoloSelector>>,
+    ReturnType<SoloSelector>,
+    OverrideMemoizeFunction,
+    OverrideArgsMemoizeFunction
+  > &
+    InterruptRecursion
+}
+
+type ParametersToVirtualInputSelectors<T extends [...any]> = {
+  [K in keyof T]: K extends keyof Array<any> ? T[K] : (...params: T) => T[K]
 }
 
 let globalStabilityCheck: StabilityCheckFrequency = 'once'

src/utils.ts

@@ -110,6 +110,11 @@ export function collectInputSelectorResults(
 ) {
   const inputSelectorResults = []
   const { length } = dependencies
+  if (!length) {
+    // no input selectors -> only one selector function was passed to `createSelector`
+    // pass all arguments to that selector function
+    return [...inputSelectorArgs]
+  }
   for (let i = 0; i < length; i++) {
     // @ts-ignore
     // apply arguments instead of spreading and mutate a local list of params for performance.

test/reselect.spec.ts

@@ -189,6 +189,11 @@ describe('Basic selector behavior', () => {
     expect(selector.recomputations()).toBe(2)
   })
 
+  test('only a result function is passed in, no input selectors', () => {
+    const selector = createSelector((a: string, b: number, c: string) => `${a}|${b}|${c}`)
+    expect(selector('foo', 3, 'baz')).toBe('foo|3|baz')
+  })
+
   test('can accept props', () => {
     let called = 0
     const selector = createSelector(