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Re: Date Conversion ?

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Thomas 'PointedEars' Lahn wrote:

> Bjoern Hoehrmann wrote:
>> A simple solution would be to use a Regex to split the value into its
>> components and converting into a form like `yyyymmdd`. You can then use
>> string comparison to find the minimum and maximum value (you could sort
>> the values but that has non-linear worst case behavior). In Perl,
>> 
>>   my ($m, $d, $y) = m#(\S+)\s+(\d+)/(\d+)#;
>>   $m = {
>>     Jan => 1,
>>     Feb => 2,
>>     ...
>>   }->{$m};
>> 
>>   my $comparable = sprintf "%04u%02u%02u", $y, $m, $d;
>> 
>> […]
> 
> In JavaScript 1.5 and later, as in other implementations of ECMAScript

Edition _3_ and later,

> you can do much the same as in Perl:
> 
>   […]
>     /*
>      * or
> 
>          var m = ({
>            "Jan": 1,
>            "Feb": 2,
>            …
>          })[matches.groups["m"]];
> 
>      * with JSX:regexp.js [2]
>      */
>     var m = ({
>       "Jan": 1,
>       "Feb": 2,
>       …
>     })[matches[0]];

    var m = {
      "Jan": 1,
      "Feb": 2,
      …
    }[matches[0]];

(and similar; without parentheses) suffices because the right-hand side of 
the assignment is evaluated in Expression context, not Statement context.

This is different with

  var s = '{"foo": "bar"}';
  
  /* Syntax error in the /Program/ parsed by eval() */
  var o = eval(s):

  /* Correct syntax in the /Program/ parsed by eval() */
  var o = eval("(" + s + ")"):

– as an insecure but backwards-compatible stand-in for JSON.parse() – and 
when for some reason you want to access a specific object referred by 
another object's property, based on a name:

  var s = "foo";

  {
    "foo": ["baz", "bar"]
  }[s].sort();
 
is a Syntax error;

  var s = "foo";

  ({
    "foo": ["baz", "bar"]
  })[s].sort();

is not.

-- 
PointedEars

Twitter: @PointedEars2
Please do not Cc: me. / Bitte keine Kopien per E-Mail.

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Date Conversion ? "Mel Smith" <med_cutout_syntel@aol.com> - 2013-12-16 15:55 -0700
  Re: Date Conversion ? Bjoern Hoehrmann <bjoern@hoehrmann.de> - 2013-12-17 01:06 +0100
    Re: Date Conversion ? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-12-19 12:34 +0100
      Re: Date Conversion ? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-12-20 22:29 +0100
        Re: Date Conversion ? Joao Rodrigues <groups_jr-1@yahoo.com.br> - 2013-12-23 10:00 -0200
  Re: Date Conversion ? JJ <duh@nah.meh> - 2013-12-17 07:06 +0700
    Re: Date Conversion ? Denis McMahon <denismfmcmahon@gmail.com> - 2013-12-17 00:35 +0000
      Re: Date Conversion ? "Mel Smith" <med_cutout_syntel@aol.com> - 2013-12-16 18:16 -0700
      Re: Date Conversion ? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2013-12-17 10:09 +0100
        Re: Date Conversion ? Denis McMahon <denismfmcmahon@gmail.com> - 2013-12-17 17:02 +0000
        Re: Date Conversion ? Dr J R Stockton <reply1300@merlyn.demon.co.uk.invalid> - 2013-12-18 19:14 +0000
          Re: Date Conversion ? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2013-12-19 15:42 +0100
            Re: Date Conversion ? "Michael F. Stemper" <michael.stemper@gmail.com> - 2013-12-19 09:20 -0600
              Re: Date Conversion ? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2013-12-20 10:04 +0100
      Re: Date Conversion ? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-12-17 15:12 +0100
        Re: Date Conversion ? Joao Rodrigues <groups_jr-1@yahoo.com.br> - 2013-12-17 18:10 -0200
          Re: Date Conversion ? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-12-17 21:42 +0100
    Re: Date Conversion ? Bjoern Hoehrmann <bjoern@hoehrmann.de> - 2013-12-18 13:36 +0100
  Re: Date Conversion ? Dr J R Stockton <reply1300@merlyn.demon.co.uk.invalid> - 2013-12-17 19:02 +0000
    Re: Date Conversion ? "Mel Smith" <med_cutout_syntel@aol.com> - 2013-12-17 20:51 -0700
      Re: Date Conversion ? Dr J R Stockton <reply1300@merlyn.demon.co.uk.invalid> - 2013-12-19 20:21 +0000
        Re: Date Conversion ? "Mel Smith" <med_cutout_syntel@aol.com> - 2013-12-20 09:52 -0700
          Re: Date Conversion ? Dr J R Stockton <reply1300@merlyn.demon.co.uk.invalid> - 2013-12-21 20:41 +0000
            Re: Date Conversion ? "Mel Smith" <med_cutout_syntel@aol.com> - 2013-12-22 09:52 -0700

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