it does seem that typemin and typemax of Date are rather large. It also 
implies that a DateTime can not contain all possible Dates. Given the 
following



julia> typemin( DateTime )
-146138511-01-01T00:00:00


julia> typemax( DateTime )
146138512-12-31T23:59:59


I was surprised to see negative values rather than the type being a UInt64. 
But is somewhat makes sense as the types are wrappers on periods for period 
math. So perhaps the issue is that typemin should be floored at zero ? 


On Monday, August 31, 2015 at 5:37:16 PM UTC-4, Jeffrey Sarnoff wrote:
>
>
> What is the utility of a date that predates the advent of time?
>
> On Friday, August 28, 2015 at 12:23:28 PM UTC-4, Michael Francis wrote:
>>
>> I agree except that people may expect yy-mm-dd to truncate, likely one of 
>> the reasons for the ccyy-mm-dd strict form. Where yy is defined as the two 
>> digit year. 
>>
>> On Friday, August 28, 2015 at 11:51:14 AM UTC-4, Stefan Karpinski wrote:
>>>
>>> The safest option is probably to raise an error.
>>>
>>> On Fri, Aug 28, 2015 at 11:47 AM, Jacob Quinn <[email protected]> wrote:
>>>
>>>> Hmmmmm.......it's not entirely clear to me what we should do here.
>>>>
>>>> On the one hand, when you ask to have the typemax(Date) formatted, it's 
>>>> currently doing what you asked, "formatting the year with 4 digits". 
>>>> Because your year in this case is greater than 4 digits, that results in 
>>>> truncation, which probably isn't what you want. But is it ok to give you 
>>>> all the digits even though you only asked for 4? I'd appreciate any other 
>>>> thoughts/input on this.
>>>>
>>>> I do think the Date/DateTime parsing/formatting code needs another once 
>>>> over to polish it up, so any ideas on allowing more 
>>>> flexibility/functionality would be appreciated.
>>>>
>>>> -Jacob
>>>>
>>>>
>>>>
>>>> On Friday, August 28, 2015 at 9:33:25 AM UTC-6, Michael Francis wrote:
>>>>>
>>>>> It seems that there is an issue with typemax of dates and string 
>>>>> representation
>>>>>
>>>>> julia> using Dates
>>>>>
>>>>>
>>>>> julia> Dates.format(typemax( Date ),"yyyy-mm-dd" )
>>>>> "1149-12-31"
>>>>>
>>>>>
>>>>> julia> typemax( Date )
>>>>> 252522163911149-12-31
>>>>>
>>>>>
>>>>> julia> Dates.format(typemax( Date ),"yyyyyyyyyyyyyyy-mm-dd" )
>>>>> "252522163911149-12-31"
>>>>>
>>>>> This hidden truncation seems dangerous. Has anybody else seen this ? 
>>>>>
>>>>
>>>

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