javascript - Are arrow functions optimized like named functions? -

i watching nodejs interactive talk , guy speaking saying how anonymous functions bad 1 of reasons being if have no name, vm cannot optimize function based on how it's used because nameless.

so if function name called

random.async('blah', function randomfunc() {});

randomfunc can optimized function like:

random.async('blah', function(cb) {});

this not optimized because it's anonymous, nameless.

so wondering if arrow functions same thing because don't think can name arrow functions.

will

random.async('blah', (cb) => {}); optimized?

edit: looking link talk guy mentions this, report back. (this talk while ago , remembered it)

edit found video: https://youtu.be/_0w_822dijg?t=299

note, not entirely these pattern comparisons discussed @ linked video presentation.

at 10000 iterations, named function appears complete fastest @ v8 implementation @ chromium. arrow function appeared return results in less time anonymous function.

at 100000 iterations anonymous function completed in briefest time; 64.51ms less named function, while arrow function took 4902.01ms more time complete named function.

    var len = array.from({        length: 100000      })         // named function      function _named() {          console.profile("named function");        console.time("named function");          function resolver(resolve, reject) {          resolve("named function")        }          function done(data) {          console.log(data)        }          function complete() {          console.timeend("named function");          console.profileend();          return "named function complete"        }          function callback() {          return new promise(resolver).then(done)        }          return promise.all(len.map(callback)).then(complete);      }         // anonymous function      function _anonymous() {        console.profile("anonymous function");        console.time("anonymous function");          return promise.all(len.map(function() {            return new promise(function(resolve, reject) {                resolve("anonymous function")              })              .then(function(data) {                console.log(data)              })          }))          .then(function() {            console.timeend("anonymous function");            console.profileend();            return "anonymous function complete"          })      }         // arrow function      function _arrow() {        console.profile("arrow function");        console.time("arrow function");          return promise.all(len.map(() => {            return new promise((resolve, reject) =>                resolve("arrow function")              )              .then((data) => {                console.log(data)              })          }))          .then(() => {            console.timeend("arrow function");            console.profileend();            return "arrow function complete"          })      }        _named().then(_anonymous).then(_arrow)

jsfiddle https://jsfiddle.net/oj87s38t/