fix: improved typings

GabeDuarteM · Apr 6, 2019 · 84dc37a · 84dc37a
1 parent a994f72
commit 84dc37a
Showing 1 changed file with 110 additions and 1 deletion.
diff --git a/src/index.ts b/src/index.ts
@@ -1,4 +1,113 @@
-const pipe = <T>(initialValue: T, ...args: any[]): any => {
+export type PipeFn<ReceivedValue, ReturnedValue> = (
+  value: ReceivedValue,
+) => ReturnedValue
+
+function pipe<T, V0>(initialValue: T, ...args: [PipeFn<T, V0>]): V0
+function pipe<T, V0, V1>(
+  initialValue: T,
+  ...args: [PipeFn<T, V0>, PipeFn<V0, V1>]
+): V1
+function pipe<T, V0, V1, V2>(
+  initialValue: T,
+  ...args: [PipeFn<T, V0>, PipeFn<V0, V1>, PipeFn<V1, V2>]
+): V2
+function pipe<T, V0, V1, V2, V3>(
+  initialValue: T,
+  ...args: [PipeFn<T, V0>, PipeFn<V0, V1>, PipeFn<V1, V2>, PipeFn<V2, V3>]
+): V3
+function pipe<T, V0, V1, V2, V3, V4>(
+  initialValue: T,
+  ...args: [
+    PipeFn<T, V0>,
+    PipeFn<V0, V1>,
+    PipeFn<V1, V2>,
+    PipeFn<V2, V3>,
+    PipeFn<V3, V4>
+  ]
+): V4
+function pipe<T, V0, V1, V2, V3, V4, V5>(
+  initialValue: T,
+  ...args: [
+    PipeFn<T, V0>,
+    PipeFn<V0, V1>,
+    PipeFn<V1, V2>,
+    PipeFn<V2, V3>,
+    PipeFn<V3, V4>,
+    PipeFn<V4, V5>
+  ]
+): V5
+function pipe<T, V0, V1, V2, V3, V4, V5, V6>(
+  initialValue: T,
+  ...args: [
+    PipeFn<T, V0>,
+    PipeFn<V0, V1>,
+    PipeFn<V1, V2>,
+    PipeFn<V2, V3>,
+    PipeFn<V3, V4>,
+    PipeFn<V4, V5>,
+    PipeFn<V5, V6>
+  ]
+): V6
+function pipe<T, V0, V1, V2, V3, V4, V5, V6, V7>(
+  initialValue: T,
+  ...args: [
+    PipeFn<T, V0>,
+    PipeFn<V0, V1>,
+    PipeFn<V1, V2>,
+    PipeFn<V2, V3>,
+    PipeFn<V3, V4>,
+    PipeFn<V4, V5>,
+    PipeFn<V5, V6>,
+    PipeFn<V6, V7>
+  ]
+): V7
+function pipe<T, V0, V1, V2, V3, V4, V5, V6, V7, V8>(
+  initialValue: T,
+  ...args: [
+    PipeFn<T, V0>,
+    PipeFn<V0, V1>,
+    PipeFn<V1, V2>,
+    PipeFn<V2, V3>,
+    PipeFn<V3, V4>,
+    PipeFn<V4, V5>,
+    PipeFn<V5, V6>,
+    PipeFn<V6, V7>,
+    PipeFn<V7, V8>
+  ]
+): V8
+function pipe<T, V0, V1, V2, V3, V4, V5, V6, V7, V8, V9>(
+  initialValue: T,
+  ...args: [
+    PipeFn<T, V0>,
+    PipeFn<V0, V1>,
+    PipeFn<V1, V2>,
+    PipeFn<V2, V3>,
+    PipeFn<V3, V4>,
+    PipeFn<V4, V5>,
+    PipeFn<V5, V6>,
+    PipeFn<V6, V7>,
+    PipeFn<V7, V8>,
+    PipeFn<V8, V9>
+  ]
+): V9
+function pipe<T, V0, V1, V2, V3, V4, V5, V6, V7, V8, V9, V10>(
+  initialValue: T,
+  ...args: [
+    PipeFn<T, V0>,
+    PipeFn<V0, V1>,
+    PipeFn<V1, V2>,
+    PipeFn<V2, V3>,
+    PipeFn<V3, V4>,
+    PipeFn<V4, V5>,
+    PipeFn<V5, V6>,
+    PipeFn<V6, V7>,
+    PipeFn<V7, V8>,
+    PipeFn<V8, V9>,
+    PipeFn<V9, V10>
+  ]
+): V10
+function pipe<T>(initialValue: T, ...args: PipeFn<any, any>[]): any
+function pipe<T>(initialValue: T, ...args: PipeFn<any, any>[]): any {
   const finalValue = args.reduce((value, func) => {
     const nextValue = func(value)