Addressed feedback.

DanielRosenwasser · DanielRosenwasser · commit 325f4b84cf6c · 2017-07-11T15:32:31.000-07:00
diff --git a/src/compiler/core.ts b/src/compiler/core.ts
@@ -703,7 +703,8 @@ namespace ts {
     export function sum<T extends Record<K, number>, K extends string>(array: T[], prop: K): number {
         let result = 0;
         for (const v of array) {
-            result += (v[prop] as number);
+            // Note: we need the following type assertion because of GH #17069
+            result += v[prop] as number;
         }
         return result;
     }

Original file line number	Diff line number	Diff line change
`@@ -703,7 +703,8 @@ namespace ts {`
`703`	`703`	`export function sum<T extends Record<K, number>, K extends string>(array: T[], prop: K): number {`
`704`	`704`	`let result = 0;`
`705`	`705`	`for (const v of array) {`
`706`		`- result += (v[prop] as number);`
	`706`	`+ // Note: we need the following type assertion because of GH #17069`
	`707`	`+ result += v[prop] as number;`
`707`	`708`	`}`
`708`	`709`	`return result;`
`709`	`710`	`}`