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Re: Reach a digit of numerical value in array index.

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Thomas 'PointedEars' Lahn wrote:
> Dr J R Stockton wrote:
>

>> Consider and test
>>
>>
>>          j = 3
>>          n = 12345 ; X = (n % Math.pow(10, j)).toString().charAt(0)
>>          n = 12045 ; Y = (n % Math.pow(10, j)).toString().charAt(0)
>>          n = 00345 ; Z = (n % Math.pow(10, j)).toString().charAt(0)
>>          Z = [X, Y, Z]        ///// ->    3, 4, 2
>
> Right, you would need to pad the toString() result if the result of the “%”
> operation would be smaller than the 1-based index (j).  I *did* test this
> approach before posting it – even though I also *did* point out *twice* that
> it is error-prone –, but not with such numbers.
>

<snip>

>
> Numeric integer literals with leading zero are parsed as octal in Mozilla
> JavaScript (and not a syntax error) when not in strict mode.  No surprise
> here.
>
>> **TESTED** in current Firefox.
>
> Confirmed in Iceweasel 31.5.0 <snip>
>

Confirmed in Chrome 41 and IE 11 as well.

   0345 // 229 [Z]
   03458 // 3458
   077 // 63
   078 // 78
   01234567 // 342391
   012345678 // 12345678
   0123456789 // 123456789

[1] <http://ecma-international.org/ecma-262/5.1/#sec-7.8.3>
     <http://ecma-international.org/ecma-262/5.1/#sec-B.1.1>

A conforming implementation, when processing strict mode code (#10.1.1), 
must not extend the syntax of NumericLiteral to include 
OctalIntegerLiteral as described in B.1.1.

In ECMAScript 6, octal number syntax uses a leading zero followed by a 
lowercase or uppercase Latin letter "O" (0o or 0O).


-- 
Joao Rodrigues

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Reach a digit of numerical value in array index. jonas.thornvall@gmail.com - 2015-03-17 14:15 -0700
  Re: Reach a digit of numerical value in array index. jonas.thornvall@gmail.com - 2015-03-17 14:34 -0700
    Re: Reach a digit of numerical value in array index. JJ <jj4public@vfemail.net> - 2015-03-18 13:38 +0700
      Re: Reach a digit of numerical value in array index. jonas.thornvall@gmail.com - 2015-03-18 06:57 -0700
  Re: Reach a digit of numerical value in array index. Norman Peelman <npeelman@cfl.rr.com> - 2015-03-18 23:49 -0400
    Re: Reach a digit of numerical value in array index. jonas.thornvall@gmail.com - 2015-03-19 01:16 -0700
      Re: Reach a digit of numerical value in array index. John Harris <niam@jghnorth.org.uk.invalid> - 2015-03-19 09:28 +0000
        Re: Reach a digit of numerical value in array index. jonas.thornvall@gmail.com - 2015-03-19 05:00 -0700
          Re: Reach a digit of numerical value in array index. John Harris <niam@jghnorth.org.uk.invalid> - 2015-03-19 16:23 +0000
            Re: Reach a digit of numerical value in array index. jonas.thornvall@gmail.com - 2015-03-19 10:43 -0700
              Re: Reach a digit of numerical value in array index. "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-03-19 19:51 +0100
              Re: Reach a digit of numerical value in array index. John Harris <niam@jghnorth.org.uk.invalid> - 2015-03-22 11:20 +0000
                Re: Reach a digit of numerical value in array index. jonas.thornvall@gmail.com - 2015-03-22 08:18 -0700
        Re: Reach a digit of numerical value in array index. Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-03-19 15:59 +0100
          Re: Reach a digit of numerical value in array index. Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-03-19 16:13 +0100
          Re: Reach a digit of numerical value in array index. Dr J R Stockton <reply1500@merlyn.demon.co.uk.invalid> - 2015-03-20 23:50 +0000
            Re: Reach a digit of numerical value in array index. Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-03-22 16:29 +0100
              Re: Reach a digit of numerical value in array index. Scott Sauyet <scott@sauyet.com> - 2015-03-22 17:36 -0400
              Re: Reach a digit of numerical value in array index. Joao Rodrigues <groups_jr-1@yahoo.com.br> - 2015-03-22 21:26 -0300
                Re: Reach a digit of numerical value in array index. Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-03-23 05:54 +0100

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