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From: "Christoph M. Becker" <cmbecker69@arcor.de>
Newsgroups: comp.lang.javascript
Subject: Re: function to get frequencies of a char array
Date: Tue, 27 Jan 2015 19:35:20 +0100
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Thomas 'PointedEars' Lahn wrote:

> Christoph M. Becker wrote:
>
>> As we were talking about array *indexes*[1], values equal to or beyond
>> 2³² are irrelevant, anyway.
>>
>> [1] <news:2697158.aGRKFDBAEn@PointedEars.de>
> 
> I do not follow.  In
> 
> |  if (e) { counts[e] ? ++counts[e] : (counts[e] = 1); }
> 
> as cited, “e” is not an array index.

To avoid the necessity to look up your code sample, I'll post the
corrected version :

  for (var i = 0, len = a.length; i < len; ++i)
  {
    /* NOTE: hasOwnProperty() may be required */
    var e = a[i];
    if (e) { counts[e] ? ++counts[e] : (counts[e] = 1); }
  }

Indeed, `e` is no array index, but `i` is.  Therefore the value of the
properties of `count` is always less than 2³² (even though it could be
greater than or equal to 2³¹).

-- 
Christoph M. Becker