++bench-instanceof-vs-obj-types.js

const assert = require('assert');

function Foo(val) {
  this.val = val;
}

const acceptInstanceOf = (cls, acceptFn, rejectFn) => {
  return v => v instanceof cls
    ? acceptFn(v)
    : rejectFn(v);
}

const acceptType = (type, acceptFn, rejectFn) => {
  return v => v.type === type
    ? acceptFn(v)
    : rejectFn(v);
}

const acceptMaybeType = (type, acceptFn, rejectFn) => {
  return v => v && v.type === type
    ? acceptFn(v)
    : rejectFn(v);
};

const fnInstance = acceptInstanceOf(Foo, v => v.val * 2, v => v * 3);
const fnType = acceptType('foo', v => v.val * 2, v => v.val * 3);
const fnMaybeType = acceptMaybeType('foo', v => v.val * 2, v => v * 3);

const test = () => {
  assert.equal(4, fnInstance(new Foo(2)), 4);
  assert.equal(6, fnInstance(2));

  assert.equal(4, fnType({
    type: 'foo',
    val: 2
  }));

  assert.equal(6, fnType({
    type: 'bar',
    val: 2
  }));

  assert.equal(4, fnMaybeType({
    type: 'foo',
    val: 2
  }));

  assert.equal(6, fnMaybeType(2));
};

suite('instanceof-vs-obj-types', () => {
  const {N = 100000} = require('./conf');

  before(() => {
    test();
  });

  bench('instanceof', () => {
    let i = -1;

    while (++i < N)
      if (i % N) fnInstance(new Foo(i));
      else fnInstance(i);
  });

  bench('type', () => {
    let i = -1;

    while (++i < N)
      if (i % N)
        fnType({
          type: 'foo',
          val: i
        });
      else
        fnType({
          type: 'bar',
          val: i
        });
  });

  bench('maybeType', () => {
    let i = -1;

    while (++i < N)
      if (i % N)
        fnType({
          type: 'foo',
          val: i
        });
      else
        fnType(i);
  });
});

+results.txt

instanceof-vs-obj-types
  instanceof ..................................... 1,000 op/s
  type ........................................... 3,168 op/s
  maybeType ...................................... 3,403 op/s

Suites:  1
Benches: 3
Elapsed: 2,641.36 ms

conf.js

let N;

if (process.env.BENCH_N) N = process.env.BENCH_N;

if (process.env.TEST) {
  set('type', 'static');
  set('iterations', 1);
  N = 1;
}

module.exports = {
  N
};

package-lock.json

{
  "name": "bench-instanceof-vs-obj-types",
  "version": "1.0.0",
  "lockfileVersion": 1,
  "requires": true,
  "dependencies": {
    "drip": {
      "version": "1.1.0",
      "resolved": "https://registry.npmjs.org/drip/-/drip-1.1.0.tgz",
      "integrity": "sha1-zO+x5obYb8EVtwyewSb4+HG9/X4=",
      "dev": true,
      "requires": {
        "tea-concat": "0.1.0"
      }
    },
    "electron": {
      "version": "0.4.1",
      "resolved": "https://registry.npmjs.org/electron/-/electron-0.4.1.tgz",
      "integrity": "sha1-p4oFGniC9OVC1uIH2KGnMHazAUQ=",
      "dev": true,
      "requires": {
        "drip": "1.1.0"
      }
    },
    "matcha": {
      "version": "0.7.0",
      "resolved": "https://registry.npmjs.org/matcha/-/matcha-0.7.0.tgz",
      "integrity": "sha1-E/gFQJs3vlcDLIRYZDvxUjumjdo=",
      "dev": true,
      "requires": {
        "electron": "0.4.1",
        "v8-argv": "0.1.0"
      }
    },
    "tea-concat": {
      "version": "0.1.0",
      "resolved": "https://registry.npmjs.org/tea-concat/-/tea-concat-0.1.0.tgz",
      "integrity": "sha1-6i6QdAD914pjNM4CD6PGlQLZnoQ=",
      "dev": true
    },
    "v8-argv": {
      "version": "0.1.0",
      "resolved": "https://registry.npmjs.org/v8-argv/-/v8-argv-0.1.0.tgz",
      "integrity": "sha1-rfd3pS29w9qciclGXlntXzy22ak=",
      "dev": true
    }
  }
}

package.json

{
  "name": "bench-instanceof-vs-obj-types",
  "version": "1.0.0",
  "description": "",
  "main": "+instanceof-vs-obj-types.js",
  "scripts": {
    "test": "TEST=1 npm run bench",
    "start": "npm run bench --silent | tee +results.txt",
    "bench": "matcha -R plain *.js"
  },
  "keywords": [],
  "author": "",
  "license": "ISC",
  "devDependencies": {
    "matcha": "^0.7.0"
  }
}