content: -----------------------------------------------------------------------------
  -- |
  -- Module      :  Data.Units.US
  -- Copyright   :  (C) 2013 Richard Eisenberg
  -- License     :  BSD-style (see LICENSE)
  -- Maintainer  :  Richard Eisenberg (rae@cs.brynmawr.edu)
  -- Stability   :  experimental
  -- Portability :  non-portable
  --
  -- This module defines the American customary system of units. Because
  -- there are some names that are conflicted, even within this system,
  -- there are several modules underneath here, defining sub-parts of
  -- the US system. This module gathers together a subjective set of
  -- units users will commonly wish to use. It also exports type instances
  -- 'DefaultUnitOfDim' that use the /SI/ internal representations. This
  -- choice is made for inter-compatibility with SI computations. If you
  -- want the foot-pound-second system, use the 'FPS'.
  --
  -- Included are all units mentioned here:
  -- <http://en.wikipedia.org/wiki/United_States_customary_units>
  -- Where possible, conversion rates have been independently verified
  -- at a US government website. However, Wikipedia's base is /much/
  -- better organized than any government resource immediately available.
  -- The US government references used are as follows:
  -- <http://nist.gov/pml/wmd/metric/upload/SP1038.pdf>
  -- <http://nist.gov/pml/wmd/pubs/upload/appc-14-hb44-final.pdf>
  -----------------------------------------------------------------------------
  
  module Data.Units.US (
    -- * Lengths
    Angstrom(..), Mil(..), Point(..), Pica(..),
    Inch(..), Foot(..), Yard(..), Mile(..), NauticalMile(..),
  
    -- * Velocity
    Knot(..),
  
    -- * Area
    Survey.Acre(..),
  
    -- * Volume
    -- | These are all /liquid/ measures. Solid measures are /different/.
    Liq.Teaspoon(..), Liq.Tablespoon(..), Liq.FluidOunce(..),
    Liq.Cup(..), Liq.Pint(..), Liq.Quart(..), Liq.Gallon(..),
  
    -- * Mass
    -- | These are all in the avoirdupois system
    Avdp.Ounce(..), Avdp.Pound(..), Avdp.Ton(..),
  
    -- * Pressure
    Atmosphere(..), Bar(..),
  
    -- * Energy
    FoodCalorie(..), Therm(..), Btu(..),
  
    -- * Power
    Horsepower(..)
    ) where
  
  import Data.Units.US.Misc
  import qualified Data.Units.US.Survey      as Survey
  import qualified Data.Units.US.Liquid      as Liq
  import qualified Data.Units.US.Avoirdupois as Avdp
  