Re: new DateTime::Format module

On Mon, 28 Jul 2008, Dan Muey wrote:

> Thanks for the feedback, I've replied inline below. Please let me know if you 
> have any other questions or suggestions.
>
> On Jul 27, 2008, at 4:12 PM, Dave Rolsky wrote:
>
>> On Sun, 27 Jul 2008, Flavio S. Glock wrote:
>> 
>>> re:
>>> http://search.cpan.org/dist/DateTime-Format-Span/
>>> 
>>> This module seems to handle durations, instead of spans.
>
> A duration is span of time no? This module uses 'span' to mean 'the duration 
> of time spanning 2 points in time' (plus ::Duration was taken)

Right, the confusion is that there is a DateTime::Span class, and I'd 
expect DateTime::Format::Span to take an object of that class and format 
it.

However, your module only operates on durations. Even more confusingly, it 
offers a "format_duration" method which only accepts a single duration, 
which is _not_ a span.

This really is not a good name for your module, because of this reason.

> The real difference is that it is simply not how a human would say it.
>
> For example from ::Duration's POD regarding its output:
> 3 years, 5 months, 1 days, 6 hours, 15 minutes, 45 seconds
> For English:
>    a) '1 days' should be '1 day'
>    b) 45 seconds should be 'and 45 seconds' (keeping the oxford comma)
>
> In my original draft I sent to Dave, when it was not under DateTime::Format 
> like it should have been, I had this in an FAQ, I should probably add it 
> back,
> Why didn't you just use 'DateTime::Format::Duration'
>
> Essencially it is a strftime for a Duration. This is not flexible enough for 
> the intent of this module.
>
> DateTime::Format::Duration is not a bad module its just for a different 
> purpose
>
> It was not localizable
> You either got '2 days' or '1 days' which a) forces it to be in English and 
> b) doesn't even make sense in English.
>
> You could get around that by adding logic each time you wanted to call it but 
> that is just messy.
>
> Had to keep an item even if it was zero
> If 'days' was in there you got '0 days', we only want items with a value to 
> show.
>
> That'd also require a lot of logic each time you wanted to call which is 
> again messy.

This all seems like it could go into DT::F::Duration though, just with 
different strftime-type specifiers (or CLDR, or whatever).

>> As far as localization, I'd prefer to see locale-specific data as part of 
>> the DateTime::Locale module itself. In fact, CLDR 1.6 does include a bunch 
>> of stuff for formatting spans in a locale-specific way. I haven't 
>> integrated that into DT::Locale yet, because I want to figure out how to 
>> actually use it.
>
> That'd be great! The way I did this for now was that ::Span::Locale 
> determined what locale to use based on the datetime object's and/or args then 
> loads Span::Locale::XX if possible and uses the data it defines.

Some of the information you define in the locale modules does exist in 
CLDR, notably singular versions of things like "day", "month", etc.

CLDR also includes formats for doing things like formatting a span based 
on the "greatest unit of differnece" between two dates. It's rather 
complicated, so I haven't implemented it yet. Basically, it lets you 
format something intelligently so you get "Jan 10-12" vs "Jan 10 - Feb 
10".


-dave

/*==========================
VegGuide.Org
Your guide to all that's veg
==========================*/