The Inbox: Chronology-Core-cmm.15.mcz

>
> Chris Muller uploaded a new version of Chronology-Core to project The Inbox:
> http://source.squeak.org/inbox/Chronology-Core-cmm.15.mcz
>
> ==================== Summary ====================
>
> Name: Chronology-Core-cmm.15
> Author: cmm
> Time: 18 October 2018, 3:06:21.843002 pm
> UUID: 388f1031-54aa-49b4-a070-726ae1d5f489
> Ancestors: Chronology-Core-tcj.12
>
> - Add Timespan>>#beCanonical so that dates created via "myDateAndTime asDate" can be made canonical.
> - A fix and optimization of Timespan>>#=.  Both elements being compared must have the same timezone (or same state of #noTimezone) in order to take advantage of the optimized #hasEqualTicks: comparison.  Otherwise (if different timezones), a full comparison of their starts (via #=) is needed.
> - There was a mention of this optimization put into the class comment.  This level of detail may be a bit tedious for users to read at that level, so Brents original comment was restored.
>
> =============== Diff against Chronology-Core-tcj.12 ===============
>
> Item was changed:
>   Magnitude subclass: #Timespan
>         instanceVariableNames: 'start duration'
>         classVariableNames: ''
>         poolDictionaries: ''
>         category: 'Chronology-Core'!
>
> + !Timespan commentStamp: 'cmm 10/17/2018 22:00' prior: 0!
> + I represent a duration starting on a specific DateAndTime.!
> - !Timespan commentStamp: 'bf 2/18/2016 14:43' prior: 0!
> - I represent a duration starting on a specific DateAndTime.
> -
> - If my start has an offset identical to my #defaultOffset then comparisons ignore timezone offset.!
>
> Item was changed:
>   ----- Method: Timespan>>= (in category 'ansi protocol') -----
>   = comparand
> +     ^ self class = comparand class
> +         and: [(((self noTimezone and: [comparand noTimezone]) or: [self start offset = comparand start offset])
> +             ifTrue: [ self start hasEqualTicks: comparand start ]
> +             ifFalse: [ self start = comparand start ])
> +         and: [ self duration = comparand duration ] ]
> -       ^ self class = comparand class
> -               and: [((self noTimezone or: [ comparand noTimezone ])
> -                       ifTrue: [ self start hasEqualTicks: comparand start ]
> -                       ifFalse: [ self start = comparand start ])
> -               and: [ self duration = comparand duration ] ]
>   .!
>
> Item was added:
> + ----- Method: Timespan>>beCanonical (in category 'squeak protocol') -----
> + beCanonical
> +       "Make the receiver a canonical Date (or Month or Year) instead of a timespan of my duration starting at a specific local time.  Canonical are the most common use of Dates in applications."
> +       self stripTimezone!
>
> Item was added:
> + ----- Method: Timespan>>stripTimezone (in category 'squeak protocol') -----
> + stripTimezone
> +       "Chronology preserves Timespans that are extracted from DateAndTime's, making Dates, Months and Years in Squeak able to represent a true Timespan of those durations starting at a specific local DateAndTime.  In case a canonical version is needed, make the receiver independent of any Timezone by removing it."
> +       start primOffset: self class defaultOffset!
>
>