From 54cdaa6951ac3b888e886e03f2e5f4301950799f Mon Sep 17 00:00:00 2001
From: Angelos Chalaris <chalarangelo@gmail.com>
Date: Sun, 4 Oct 2020 00:26:51 +0300
Subject: [PATCH] Add combine

---
 snippets/combine.md | 40 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 40 insertions(+)
 create mode 100644 snippets/combine.md

diff --git a/snippets/combine.md b/snippets/combine.md
new file mode 100644
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+++ b/snippets/combine.md
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+---
+title: combine
+tags: array,object,intermediate
+---
+
+Combines two arrays of objects, using the specified key to match objects.
+
+- Use `Array.protoype.reduce()` with an object accumulator to combine all objects in both arrays based on the given `prop`.
+- Use `Object.values()` to convert the resulting object to an array and return it.
+
+```js
+const combine = (a, b, prop) =>
+  Object.values(
+    [...a, ...b].reduce((acc, v) => {
+      if (v[prop])
+        acc[v[prop]] = acc[v[prop]]
+          ? { ...acc[v[prop]], ...v }
+          : { ...v };
+      return acc;
+    }, {})
+  );
+```
+
+```js
+const x = [
+  { id: 1, name: 'John' },
+  { id: 2, name: 'Maria' }
+];
+const y = [
+  { id: 1, age: 28 },
+  { id: 3, age: 26 },
+  { age: 3}
+];
+combine(x, y, 'id');
+// [
+//  { id: 1, name: 'John', age: 28 },
+//  { id: 2, name: 'Maria' },
+//  { id: 3, age: 26 }
+// ]
+```