new file: javascript/sort-alphabetically.md

javascript/sort-alphabetically.md

@@ -0,0 +1,40 @@
+# Sort Alphabetically
+
+```javascript
+const people = [
+  { firstName: "Aaron", lastName: "Smith" },
+  { firstName: "Émile", lastName: "Zola" },
+  { firstName: "Charlotte", lastName: "Brown" },
+  { firstName: "Beyoncé", lastName: "Knowles" },
+  { firstName: "Ólafur", lastName: "Arnalds" },
+  { firstName: "David", lastName: "Jones" },
+  { firstName: "Zoë", lastName: "Deschanel" },
+];
+
+function sortAlphabetically(arr) {
+  return arr.sort((a, b) => {
+    if (a.firstName < b.firstName) {
+      return -1;
+    }
+
+    if (a.firstName > b.firstName) {
+      return 1;
+    }
+
+    return 0;
+  });
+}
+
+sortAlphabetically(people);
+```
+
+By default, string comparison in JavaScript is not language-sensitive (meaning it doesn’t take into account language-specific rules or special characters like accents), which results in the sorted list not being in the correct order.
+
+The solution is to leverage `Intl.Collator` which enables language-sensitive string comparison.
+
+```javascript
+function sortAlphabetically(arr) {
+  const collator = new Intl.Collator("en", { sensitivity: "base" });
+  return arr.sort((a, b) => collator.compare(a.firstName, b.firstName));
+}
+```

javascript/sort-numbers.md

@@ -1,4 +1,4 @@
-# Sort array of numbers
+# Sort Array of Numbers
 
 In javascript, the `Array` `sort` function will cast everything to a string. So when you have an array of numbers, you need to repetitively cast them to numbers: