From e4ec2b98a216cf61762aac73be83016b8e581e33 Mon Sep 17 00:00:00 2001
From: Daniel Cassidy <mail@danielcassidy.me.uk>
Date: Fri, 19 Apr 2019 10:06:19 +0100
Subject: [PATCH] feat(groupBy): accept any ArrayLike as argument

---
 index.ts    | 7 ++++---
 tslint.json | 5 ++++-
 2 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/index.ts b/index.ts
index fe47d0a6..7246e65a 100644
--- a/index.ts
+++ b/index.ts
@@ -38,11 +38,12 @@ export function reverseFn(): typeof reverse {
     return reverse;
 }
 
-export function groupBy<TElement>(array: ReadonlyArray<TElement>,
+export function groupBy<TElement>(array: ArrayLike<TElement>,
                                   keyOf: (element: TElement) => string): Dictionary<TElement[]> {
     const grouped = {} as Dictionary<TElement[]>;
 
-    for (const element of array) {
+    for (let i = 0; i < array.length; ++i) {
+        const element = array[i];
         const key = keyOf(element);
         const group = grouped[key] || [];
         group.push(element);
@@ -52,7 +53,7 @@ export function groupBy<TElement>(array: ReadonlyArray<TElement>,
     return grouped;
 }
 
-export function groupByFn<T>(keyOf: (element: T) => string): (array: ReadonlyArray<T>) => Dictionary<T[]> {
+export function groupByFn<T>(keyOf: (element: T) => string): (array: ArrayLike<T>) => Dictionary<T[]> {
     return array => groupBy(array, keyOf);
 }
 
diff --git a/tslint.json b/tslint.json
index b55edf6c..fbdb5274 100644
--- a/tslint.json
+++ b/tslint.json
@@ -1,3 +1,6 @@
 {
-  "extends": "@softwareventures/tslint-rules"
+  "extends": "@softwareventures/tslint-rules",
+  "rules": {
+    "prefer-for-of": false
+  }
 }
\ No newline at end of file