# time-interval: Use a time unit class, but hold a concrete time type.

[ data, library, public-domain ] [ Propose Tags ]

Two common ways to represent and hold short time intervals seem to be:

1. Hold time in microseconds as an Int or Integer

2. Use time units abstraction, e.g. see the time-units package

While the second option is a great abstraction to use in APIs, it works for datatypes a bit less well than for function types. That's because a datatype which a Data.Time.Units.TimeUnit field suddenly becomes polymorphic over that field, and all function type signatures involving that datatype need to be updated. This is less an issue for functions, because you don't specify the type of every function at the call site.

Perhaps there is a solution for that which involves datatype related language extensions, but this package tries to offer a simple clean solution as follows. You store time in your datatype as an integer, but it is wrapped by an opaque Data.Time.Interval.TimeInterval type. You then get the best of both worlds:

• On one hand, you can set the time field using any time unit thanks to the time-units package, so you get a nice abstraction

• On the other hand, your datatype holds a concrete time type

The time type can be equally used to represent time intervals, time durations and generally time lengths. But since high precision is used (microseconds), you'll probably want this library for short time lengths (at most seconds, minutes, hours). For calendar based and related time functions and types, see the time package.

Versions [faq] 0.1.0.0, 0.1.1 ChangeLog base (>=4.7 && <5), time-units [details] LicenseRef-PublicDomain ♡ Copying is an act of love. Please copy, reuse and share. fr33domlover fr33domlover@riseup.net Data http://hub.darcs.net/fr33domlover/time-interval mailto:fr33domlover@riseup.net head: darcs get http://hub.darcs.net/fr33domlover/time-interval by akrasner at Mon May 30 06:56:54 UTC 2016 NixOS:0.1.1 1341 total (39 in the last 30 days) (no votes yet) [estimated by rule of succession] λ λ λ Docs available Last success reported on 2016-05-30

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