penny-lib-0.14.0.0: Extensible double-entry accounting system - library
Penny.Lincoln.Bits.Price
Synopsis
newtype From Source
Constructors
Fields
Instances
newtype To Source
newtype CountPerUnit Source
data Price Source
Two Price are equivalent if the From and To are equal and the CountPerUnit is equivalent.
newPrice :: From -> To -> CountPerUnit -> Maybe PriceSource
Succeeds only if From and To are different commodities.