feat(api): add bench() & timed() utils

packages/api/src/bench.ts

@@ -0,0 +1,29 @@
+/**
+ * Calls function `fn` without args, prints elapsed time and returns
+ * fn's result.
+ *
+ * @param fn
+ */
+export function timed<T>(fn: () => T) {
+    const t0 = Date.now();
+    const res = fn();
+    console.log(Date.now() - t0);
+    return res;
+}
+
+/**
+ * Executes given function `n` times, prints elapsed time to console and
+ * returns last result from fn.
+ *
+ * @param fn
+ * @param n
+ */
+export function bench<T>(fn: () => T, n = 1e6) {
+    let res: T;
+    return timed(() => {
+        while (n-- > 0) {
+            res = fn();
+        }
+        return res;
+    });
+}

packages/api/src/index.ts

@@ -2,6 +2,7 @@ import * as decorators from "./decorators";
 import * as mixins from "./mixins";
 
 export * from "./api";
+export * from "./bench";
 export * from "./compare";
 export * from "./error";
 export * from "./equiv";