init commit

1 files changed, 33 insertions, 0 deletions

diff --git a/src/utils/array.ts b/src/utils/array.ts
new file mode 100644
index 0000000..de9ef96
--- /dev/null
+++ b/src/utils/array.ts
@@ -0,0 +1,33 @@
+/**
+ * Split an array into two groups based on the result {@linkcode predicate}
+ *
+ * Items for which {@linkcode predicate} returns `true` will be in the "left"
+ * result, and the others in the "right" one
+ */
+export function partition<T>(
+    input: Array<T>,
+    predicate: (element: T) => boolean,
+): [Array<T>, Array<T>] {
+    const left: Array<T> = [];
+    const right: Array<T> = [];
+
+    for (const element of input) {
+        if (predicate(element)) {
+            left.push(element);
+        } else {
+            right.push(element);
+        }
+    }
+
+    return [left, right];
+}
+
+/**
+ * Deduplicate the elements of {@linkcode items} by their `id` property
+ */
+export function uniqueById<T extends { id: string }>(items: T[]): T[] {
+    const entries = items.map((item) => [item.id, item] as const);
+    const mapById = new Map<string, T>(entries);
+
+    return Array.from(mapById.values());
+}