Can't enable tail call optimization in node v6.4.0

Question

I wan't to play around with tail call optimization in node/es2015, but I keep getting

RangeError: Maximum call stack size exceeded

. So I tried a very simple test function:

  function countTo(n, acc) {

    if(n === 0) {

      return acc;

    }

    return countTo(n - 1, acc + n);

  }



  console.log(countTo(100000 , 0))

and it still fails. I've tried adding

'use strict';

inside the function body and at the top of the file. I've tried using

--harmony

and

--harmony-tailcalls

The same function works as expected in racket:

#lang racket

(define count-to

  (lambda (n acc)

    (cond

      ((= n 0) acc)

      (else (count-to (- n 1) (+ acc n))))))

(count-to 100000000 0)

; ~> 5000000050000000

Edit:

As @MatthieuLemoine suggested. It works in v6.5.0+ with
`"use strict";`
and either
`--harmony`
or
`--harmony-tailcalls`

Answer 1

Using node v6.5.0, the following works :

function countTo(n, acc) {
  'use strict';
  if(n === 0) {
    return acc;
  }
  return countTo(n - 1, acc + n);
}
console.log(countTo(100000 , 0));

Running with --harmony-tailcalls flag :

node --harmony-tailcalls tco.js

Can't enable tail call optimization in node v6.4.0

Edit:

As @MatthieuLemoine suggested. It works in v6.5.0+ with "use strict"; and either --harmony or --harmony-tailcalls

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As @MatthieuLemoine suggested. It works in v6.5.0+ with
`"use strict";`
and either
`--harmony`
or
`--harmony-tailcalls`