From 26d632b5f4433ec98028e2037950614be644d151 Mon Sep 17 00:00:00 2001
From: Stephen King <stephen@footstepsmarketing.com>
Date: Fri, 9 Jun 2017 15:44:58 -0600
Subject: [PATCH] ramda: Allow currying of type guards

---
 types/ramda/index.d.ts     | 46 +++++++++++++++++++++++++++++++++++++-
 types/ramda/ramda-tests.ts | 19 ++++++++++++++++
 2 files changed, 64 insertions(+), 1 deletion(-)

diff --git a/types/ramda/index.d.ts b/types/ramda/index.d.ts
index 9666c1b78f..79d1b1f6cf 100644
--- a/types/ramda/index.d.ts
+++ b/types/ramda/index.d.ts
@@ -1,6 +1,10 @@
 // Type definitions for ramda
 // Project: https://github.com/donnut/typescript-ramda
-// Definitions by: Erwin Poeze <https://github.com/donnut>, Matt DeKrey <https://github.com/mdekrey>, Liam Goodacre <https://github.com/LiamGoodacre>, Matt Dziuban <https://github.com/mrdziuban>
+// Definitions by: Erwin Poeze <https://github.com/donnut>
+//                 Matt DeKrey <https://github.com/mdekrey>
+//                 Liam Goodacre <https://github.com/LiamGoodacre>
+//                 Matt Dziuban <https://github.com/mrdziuban>
+//                 Stephen King <https://github.com/sbking>
 // Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
 // TypeScript Version: 2.2
 
@@ -75,6 +79,41 @@ declare namespace R {
     }
 
     // @see https://gist.github.com/donnut/fd56232da58d25ceecf1, comment by @albrow
+    interface CurriedTypeGuard2<T1, T2, R extends T2> {
+        (t1: T1): (t2: T2) => t2 is R;
+        (t1: T1, t2: T2): t2 is R;
+    }
+
+    interface CurriedTypeGuard3<T1, T2, T3, R extends T3> {
+        (t1: T1): CurriedTypeGuard2<T2, T3, R>;
+        (t1: T1, t2: T2): (t3: T3) => t3 is R;
+        (t1: T1, t2: T2, t3: T3): t3 is R;
+    }
+
+    interface CurriedTypeGuard4<T1, T2, T3, T4, R extends T4> {
+        (t1: T1): CurriedTypeGuard3<T2, T3, T4, R>;
+        (t1: T1, t2: T2): CurriedTypeGuard2<T3, T4, R>;
+        (t1: T1, t2: T2, t3: T3): (t4: T4) => t4 is R;
+        (t1: T1, t2: T2, t3: T3, t4: T4): t4 is R;
+    }
+
+    interface CurriedTypeGuard5<T1, T2, T3, T4, T5, R extends T5> {
+        (t1: T1): CurriedTypeGuard4<T2, T3, T4, T5, R>;
+        (t1: T1, t2: T2): CurriedTypeGuard3<T3, T4, T5, R>;
+        (t1: T1, t2: T2, t3: T3): CurriedTypeGuard2<T4, T5, R>;
+        (t1: T1, t2: T2, t3: T3, t4: T4): (t5: T5) => t5 is R;
+        (t1: T1, t2: T2, t3: T3, t4: T4, t5: T5): t5 is R;
+    }
+
+    interface CurriedTypeGuard6<T1, T2, T3, T4, T5, T6, R extends T6> {
+        (t1: T1): CurriedTypeGuard5<T2, T3, T4, T5, T6, R>;
+        (t1: T1, t2: T2): CurriedTypeGuard4<T3, T4, T5, T6, R>;
+        (t1: T1, t2: T2, t3: T3): CurriedTypeGuard3<T4, T5, T6, R>;
+        (t1: T1, t2: T2, t3: T3, t4: T4): CurriedTypeGuard2<T5, T6, R>;
+        (t1: T1, t2: T2, t3: T3, t4: T4, t5: T5): (t6: T6) => t6 is R;
+        (t1: T1, t2: T2, t3: T3, t4: T4, t5: T5, t6: T6): t6 is R;
+    }
+
     interface CurriedFunction2<T1, T2, R> {
         (t1: T1): (t2: T2) => R;
         (t1: T1, t2: T2): R;
@@ -392,6 +431,11 @@ declare namespace R {
          * Returns a curried equivalent of the provided function. The curried function has two unusual capabilities.
          * First, its arguments needn't be provided one at a time.
          */
+        curry<T1, T2, TResult extends T2>(fn: (a: T1, b: T2) => b is TResult): CurriedTypeGuard2<T1,T2, TResult>
+        curry<T1, T2, T3, TResult extends T3>(fn: (a: T1, b: T2, c: T3) => c is TResult): CurriedTypeGuard3<T1,T2, T3, TResult>
+        curry<T1, T2, T3, T4, TResult extends T4>(fn: (a: T1, b: T2, c: T3, d: T4) => d is TResult): CurriedTypeGuard4<T1,T2, T3, T4, TResult>
+        curry<T1, T2, T3, T4, T5, TResult extends T5>(fn: (a: T1, b: T2, c: T3, d: T4, e: T5) => e is TResult): CurriedTypeGuard5<T1,T2, T3, T4, T5, TResult>
+        curry<T1, T2, T3, T4, T5, T6, TResult extends T6>(fn: (a: T1, b: T2, c: T3, d: T4, e: T5, f: T6) => f is TResult): CurriedTypeGuard6<T1,T2, T3, T4, T5, T6, TResult>
         curry<T1, T2, TResult>(fn: (a: T1, b: T2) => TResult): CurriedFunction2<T1,T2, TResult>
         curry<T1, T2, T3, TResult>(fn: (a: T1, b: T2, c: T3) => TResult): CurriedFunction3<T1,T2, T3, TResult>
         curry<T1, T2, T3, T4, TResult>(fn: (a: T1, b: T2, c: T3, d: T4) => TResult): CurriedFunction4<T1,T2, T3, T4, TResult>
diff --git a/types/ramda/ramda-tests.ts b/types/ramda/ramda-tests.ts
index f9b272f8ca..8fbbb5c7ba 100644
--- a/types/ramda/ramda-tests.ts
+++ b/types/ramda/ramda-tests.ts
@@ -86,6 +86,25 @@ class F2 {
     var z2:number = addTwoNumbersCurried(2,3);
 }
 
+() => {
+    interface Car { speed?: number; }
+    interface FastCar { speed: number; }
+
+    const typeGuard = function(a: number, b: number, c: number, d: number, e: number, car: Car): car is FastCar {
+      return car.speed !== undefined;
+    }
+    const typeGuardCurried = R.curry(typeGuard);
+
+    const drive = function(fastCar: FastCar) {};
+
+    const cars: Car[] = [{ speed: 65 }, {}];
+    for (const car of cars) {
+      if (typeGuardCurried(1)(2)(3)(4)(5)(car)) {
+        drive(car);
+      }
+    }
+}
+
 () => {
     const addFour = (a:number) => (b:number) => (c:number) => (d:number) => a + b + c + d;
     const uncurriedAddFour = R.uncurryN<number>(4, addFour);