Design Choices

The design choices are centered around ease of use, rather than compatibility, and browser bundling.

Months

The DateTz object treats 1 as the first month of the year, rather than 0 for the built in Date class.

Day of Week

The Date object treats 0 as Sunday, and this library accepts that convention. This means functions like startOfWeek will return Sunday rather than Monday.

No Unnecessary Functions

The addDays function has no complimentary subDays function, as this can be achieved by making the days argument negative.

Prefer Functions to Classes

While classes might provide a more elegant interface, few tree shaking libraries and able to prune unused class methods, so functions are preferred to classes.

Provide Unminified Bundle

This may change, but the current view is that the majority of developers use bundlers, rather than include manual <script> tags. With this in mind the code is provided as a single javascript file, as the downstream bundler will do the tree shaking.

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