Web view of haskell units package.
For example, say I have a Piece of String which is 1 meter long and I would like to tell my father about it. He refuses to use the metric system for any domestic or familial related matter so I have to convert the Quantity associated with the Length Dimension of the Piece of String into the Imperial System of Measurement. That means I must take the Quantity represented by (1 meter), (numerical value, unit), and convert it to a new Quantity (3.28084 feet). Note both Quantities describe an identical Physical Invariant: the Length of the Piece of String. Now I can write a letter to my father telling him about my Piece of String.