Added benchmarks.

bench/gen-fun.mjs

@@ -0,0 +1,29 @@
+import gen from 'stream-chain/gen.js';
+import fun from 'stream-chain/fun.js';
+import {getManyValues} from 'stream-chain/defs.js';
+
+const fns = [x => x - 2, x => x + 1, x => 2 * x, x => x + 2, x => x >> 1];
+
+const g = gen(...fns),
+  f = fun(...fns);
+
+export default {
+  async gen(n) {
+    let acc = 0;
+    for (let i = 0; i < n; ++i) {
+      for await (const x of g(i)) {
+        acc += x;
+      }
+    }
+    return acc;
+  },
+  async fun(n) {
+    let acc = 0;
+    for (let i = 0; i < n; ++i) {
+      for (const x of getManyValues(await f(i))) {
+        acc += x;
+      }
+    }
+    return acc;
+  }
+};

bench/gen-opt.mjs

@@ -0,0 +1,60 @@
+import gen from 'stream-chain/gen.js';
+import {clearFunctionList} from 'stream-chain/defs.js';
+
+const g1 = gen(
+    x => x - 2,
+    x => x + 1,
+    x => 2 * x,
+    x => x + 2,
+    x => x >> 1
+  ),
+  g2 = gen(
+    x => x - 2,
+    gen(
+      x => x + 1,
+      x => 2 * x,
+      x => x + 2
+    ),
+    x => x >> 1
+  ),
+  g3 = gen(
+    x => x - 2,
+    clearFunctionList(
+      gen(
+        x => x + 1,
+        x => 2 * x,
+        x => x + 2
+      )
+    ),
+    x => x >> 1
+  );
+
+export default {
+  async ['simple list'](n) {
+    let acc = 0;
+    for (let i = 0; i < n; ++i) {
+      for await (const x of g1(i)) {
+        acc += x;
+      }
+    }
+    return acc;
+  },
+  async ['optimization on'](n) {
+    let acc = 0;
+    for (let i = 0; i < n; ++i) {
+      for await (const x of g2(i)) {
+        acc += x;
+      }
+    }
+    return acc;
+  },
+  async ['optimization off'](n) {
+    let acc = 0;
+    for (let i = 0; i < n; ++i) {
+      for await (const x of g3(i)) {
+        acc += x;
+      }
+    }
+    return acc;
+  }
+};

package.json

@@ -41,6 +41,7 @@
   },
   "devDependencies": {
     "@types/node": "^22.5.5",
+    "nano-benchmark": "^1.0.2",
     "tape-six": "^0.9.6",
     "typescript": "^5.6.2"
   }