| Safe Haskell | None |
|---|---|
| Language | Haskell2010 |
Data.Money
Contents
Description
Import this module qualified:
import qualified Data.Money as Money
- data Dense currency
- dense :: Rational -> Maybe (Dense currency)
- type Discrete currency unit = Discrete' currency (Scale currency unit)
- data Discrete' currency scale
- fromDiscrete :: GoodScale scale => Discrete' currency scale -> Dense currency
- round :: GoodScale scale => Dense currency -> (Discrete' currency scale, Maybe (Dense currency))
- ceiling :: GoodScale scale => Dense currency -> (Discrete' currency scale, Maybe (Dense currency))
- floor :: GoodScale scale => Dense currency -> (Discrete' currency scale, Maybe (Dense currency))
- truncate :: GoodScale scale => Dense currency -> (Discrete' currency scale, Maybe (Dense currency))
- type family Scale (currency :: Symbol) (unit :: Symbol) :: (Nat, Nat)
- type GoodScale scale = (CmpNat 0 (Fst scale) ~ LT, CmpNat 0 (Snd scale) ~ LT, KnownNat (Fst scale), KnownNat (Snd scale))
- scale :: forall proxy scale. GoodScale scale => proxy scale -> Rational
- data ExchangeRate src dst
- exchangeRate :: Rational -> Maybe (ExchangeRate src dst)
- fromExchangeRate :: ExchangeRate src dst -> Rational
- flipExchangeRate :: ExchangeRate a b -> ExchangeRate b a
- exchange :: ExchangeRate src dst -> Dense src -> Dense dst
- data DenseRep
- denseRep :: KnownSymbol currency => Dense currency -> DenseRep
- fromDenseRep :: forall currency. KnownSymbol currency => DenseRep -> Maybe (Dense currency)
- withDenseRep :: DenseRep -> (forall currency. KnownSymbol currency => Dense currency -> r) -> r
- data DiscreteRep
- discreteRep :: (KnownSymbol currency, GoodScale scale) => Discrete' currency scale -> DiscreteRep
- fromDiscreteRep :: forall currency scale. (KnownSymbol currency, GoodScale scale) => DiscreteRep -> Maybe (Discrete' currency scale)
- withDiscreteRep :: forall r. DiscreteRep -> (forall currency scale. (KnownSymbol currency, GoodScale scale) => Discrete' currency scale -> r) -> r
- data ExchangeRateRep
- exchangeRateRep :: (KnownSymbol src, KnownSymbol dst) => ExchangeRate src dst -> ExchangeRateRep
- fromExchangeRateRep :: forall src dst. (KnownSymbol src, KnownSymbol dst) => ExchangeRateRep -> Maybe (ExchangeRate src dst)
- withExchangeRateRep :: ExchangeRateRep -> (forall src dst. (KnownSymbol src, KnownSymbol dst) => ExchangeRate src dst -> r) -> r
Dense monetary values
Dense represents a dense monetary value for currency (usually a
ISO-4217 currency code, but not necessarily) as a rational number.
While monetary values associated with a particular currency are discrete, you
can still treat monetary values as dense while operating on them. For
example, the half of USD 3.41 is USD 1.705, which is not an amount that
can't be represented as a number of USD cents (the smallest unit that can
represent USD amounts). Nevertheless, if you eventually multiply USD 1.705
by 4, for example, you end up with USD 6.82, which is again a value
representable as USD cents. In other words, Dense monetary values
allow us to perform precise calculations deferring the conversion to a
Discrete monetary values as much as posible. Once you are ready to
aproximate a Dense value to a Discrete value you can use one of
round, floor, ceiling or truncate. Otherwise, using toRational you
can obtain a precise Rational representation.
Construct Dense monetary values using dense, or
fromInteger / fromIntegral if that suffices.
WARNING if you want to treat a dense monetary value as a Real number (for
example, to take the square root of that monetary value), then you are on
your own. We can only guarantee lossless manipulation of rational values, so
you will need to convert back and forth betwen the Rational representation
for Dense and your (likely lossy) representation for Real numbers.
Instances
| Eq (Dense currency) Source # | |
| Fractional (Dense currency) Source # | |
| Num (Dense currency) Source # | |
| Ord (Dense currency) Source # | |
| KnownSymbol currency => Read (Dense currency) Source # | |
| Real (Dense currency) Source # | |
| KnownSymbol currency => Show (Dense currency) Source # | |
| Generic (Dense currency) Source # | |
| Hashable (Dense currency) Source # | |
| KnownSymbol currency => ToJSON (Dense currency) Source # | Compatible with |
| KnownSymbol currency => FromJSON (Dense currency) Source # | Compatible with |
| KnownSymbol currency => Binary (Dense currency) Source # | Compatible with |
| KnownSymbol currency => Serialize (Dense currency) Source # | Compatible with |
| NFData (Dense currency) Source # | |
| KnownSymbol currency => Store (Dense currency) Source # | Compatible with |
| type Rep (Dense currency) Source # | |
Discrete monetary values
type Discrete currency unit = Discrete' currency (Scale currency unit) Source #
Discrete represents a discrete monetary value for a currency expresed
as an integer amount of a particular unit. For example, with currency ~
"USD" and unit ~ "cent" you can represent United States Dollars to
their full extent.
currency is usually a ISO-4217 currency code, but not necessarily.
Construct Discrete values using fromInteger.
For example, if you want to represent GBP 21.05, where the smallest
represetable unit for a GBP (United Kingdom Pound) is the penny, and 100
pennies equal 1 GBP (i.e., ), then you can
use:Scale "GBP" ~ '(100, 1)
fromInteger 2105 :: Discrete "GBP" "penny"
Because 2015 / 100 == 20.15.
data Discrete' currency scale Source #
Discrete' represents a discrete monetary value for a currency expresed
as an amount of scale, which is a rational number expressed as (numerator,
denominator).
You'll be using Discrete instead of Discrete' most of the time, which
mentions the unit name (such as cent or centavo) instead of explicitely
mentioning the unit scale.
Instances
| Enum (Discrete' currency scale) Source # | |
| Eq (Discrete' currency scale) Source # | |
| TypeError Constraint ((:$$:) ((:$$:) ((:<>:) ((:<>:) ((:<>:) (Text "The ") (ShowType (Symbol -> (Nat, Nat) -> *) Discrete')) (Text " type is deliberately not a ")) (ShowType (* -> Constraint) Fractional)) ((:<>:) ((:<>:) ((:<>:) (Text "instance. Convert the ") (ShowType (Symbol -> (Nat, Nat) -> *) Discrete')) (Text " value to a ")) (ShowType (Symbol -> *) Dense))) ((:<>:) ((:<>:) (Text "value and use the ") (ShowType (* -> Constraint) Fractional)) (Text " features on it instead."))) => Fractional (Discrete' currency scale) Source # | |
| Integral (Discrete' currency scale) Source # | |
| Num (Discrete' currency scale) Source # | |
| Ord (Discrete' currency scale) Source # | |
| (KnownSymbol currency, GoodScale scale) => Read (Discrete' currency scale) Source # | |
| Real (Discrete' currency scale) Source # | |
| (KnownSymbol currency, GoodScale scale) => Show (Discrete' currency scale) Source # | |
| Generic (Discrete' currency scale) Source # | |
| Hashable (Discrete' currency scale) Source # | |
| (KnownSymbol currency, GoodScale scale) => ToJSON (Discrete' currency scale) Source # | Compatible with |
| (KnownSymbol currency, GoodScale scale) => FromJSON (Discrete' currency scale) Source # | Compatible with |
| (KnownSymbol currency, GoodScale scale) => Binary (Discrete' currency scale) Source # | Compatible with |
| (KnownSymbol currency, GoodScale scale) => Serialize (Discrete' currency scale) Source # | Compatible with |
| NFData (Discrete' currency scale) Source # | |
| (KnownSymbol currency, GoodScale scale) => Store (Discrete' currency scale) Source # | Compatible with |
| type Rep (Discrete' currency scale) Source # | |
Round a Dense value x to the nearest value fully representable in
its currency's unit Scale, which might be x itself.
If x is already fully representable in its currency's unit Scale,
then the following holds:
roundx == (x,Nothing)
Otherwise, if the nearest value to x that is fully representable in its
currency's unit Scale is greater than x, then the following holds:
round==ceiling
Otherwise, the nearest value to x that is fully representable in its
currency's unit Scale is smaller than x, and the following holds:
round==floor
Proof that round doesn't lose money:
x == caseroundx of (y,Nothing) -> y (y,Justz) -> y + z
Round a Dense value x to the nearest value fully representable in
its currency's unit Scale which is greater than x or equal to x.
If x is already fully representable in its currency's unit Scale,
then the following holds:
ceilingx == (x,Nothing)
Otherwise, if x is not representable in its currency's unit Scale,
then the following holds:
ceilingx == (y,Justz)
x /= y
z < zero
Proof that ceiling doesn't lose money:
x == caseceilingx of (y,Nothing) -> y (y,Justz) -> y + z
Round a Dense value x to the nearest value fully representable in
its currency's unit Scale which is smaller than x or equal to x.
If x is already fully representable in its currency's unit Scale,
then the following holds:
floorx == (x,Nothing)
Otherwise, if x is not representable in its currency's unit Scale,
then the following holds:
floorx == (y,Justz)
x /= y
z > zero
Proof that floor doesn't lose money:
x == casefloorx of (y,Nothing) -> y (y,Justz) -> y + z
Round a Dense value x to the nearest value between zero and
x (inclusive) which is fully representable in its currency's unit
Scale.
If x is already fully representable in its currency's unit Scale,
then the following holds:
truncatex == (x,Nothing)
Otherwise, if x is positive, then the following holds:
truncate==floor
Otherwise, if x is negative, the following holds:
truncate==ceiling
Proof that truncate doesn't lose money:
x == casetruncatex of (y,Nothing) -> y (y,Justz) -> y + z
Currency scales
type family Scale (currency :: Symbol) (unit :: Symbol) :: (Nat, Nat) Source #
is a rational number (expressed as Scale currency unit'(numerator,
denominator)) indicating how many pieces of unit fit in currency.
currency is usually a ISO-4217 currency code, but not necessarily.
The Scale will determine how to convert a Dense value into a
Discrete value and vice-versa.
For example, there are 100 USD cents in 1 USD, so the scale for this relationship is:
type instance Scale "USD" "cent" = '(100, 1)
As another example, there is 1 dollar in USD, so the scale for this relationship is:
type instance Scale "USD" "dollar" = '(1, 1)
When using Discrete values to represent money, it will be impossible to
represent an amount of currency smaller than unit. So, if you decide to
use Scale "USD" "dollar" as your scale, you will not be able to
represent values such as USD 3.50 or USD 21.87, since they are not exact
multiples of a dollar.
If there exists a cannonical smallest unit that can fully represent the
currency, then an instance exists.Scale currency currency
type instance Scale "USD" "USD" = Scale "USD" "cent"
For some monetary values, such as precious metals, the smallest representable unit is not obvious, since you can continue to split the precious metal many times before it stops being a precious metal. Still, for practical purposes we can make a sane arbitrary choice of smallest unit. For example, the base unit for XAU (Gold) is the troy ounce, which is too big to be considered the smallest unit, but we can arbitrarily choose the milligrain as our smallest unit, which is about as heavy as a single grain of table salt and should be sufficiently precise for all monetary practical purposes. A /troy ounce equals 480000 milligrains/.
type instance Scale "XAG" "milligrain" = '(480000, 1)
You can use other units such as milligrams for measuring XAU, for example. However, since the amount of milligrams in a troy ounce (31103.477) is not integral, we need to use rational number to express it.
type instance Scale "XAU" "milligram" = '(31103477, 1000)
If you try to obtain the 'Scale of a currency without an obvious smallest
representable unit, like XAU, you will get a compile error.
Instances
| type Scale "AED" "AED" Source # | |
| type Scale "AED" "dirham" Source # | |
| type Scale "AED" "fils" Source # | |
| type Scale "AFN" "AFN" Source # | |
| type Scale "AFN" "afghani" Source # | |
| type Scale "AFN" "pul" Source # | |
| type Scale "ALL" "ALL" Source # | |
| type Scale "ALL" "lek" Source # | |
| type Scale "ALL" "qindarke" Source # | |
| type Scale "AMD" "AMD" Source # | |
| type Scale "AMD" "dram" Source # | |
| type Scale "AMD" "luma" Source # | |
| type Scale "ANG" "ANG" Source # | |
| type Scale "ANG" "cent" Source # | |
| type Scale "ANG" "guilder" Source # | |
| type Scale "AOA" "AOA" Source # | |
| type Scale "AOA" "centimo" Source # | |
| type Scale "AOA" "kwanza" Source # | |
| type Scale "ARS" "ARS" Source # | |
| type Scale "ARS" "centavo" Source # | |
| type Scale "ARS" "peso" Source # | |
| type Scale "AUD" "AUD" Source # | |
| type Scale "AUD" "cent" Source # | |
| type Scale "AUD" "dollar" Source # | |
| type Scale "AWG" "AWG" Source # | |
| type Scale "AWG" "cent" Source # | |
| type Scale "AWG" "florin" Source # | |
| type Scale "AZN" "AZN" Source # | |
| type Scale "AZN" "manat" Source # | |
| type Scale "AZN" "qapik" Source # | |
| type Scale "BAM" "BAM" Source # | |
| type Scale "BAM" "fening" Source # | |
| type Scale "BAM" "mark" Source # | |
| type Scale "BBD" "BBD" Source # | |
| type Scale "BBD" "cent" Source # | |
| type Scale "BBD" "dollar" Source # | |
| type Scale "BDT" "BDT" Source # | |
| type Scale "BDT" "paisa" Source # | |
| type Scale "BDT" "taka" Source # | |
| type Scale "BGN" "BGN" Source # | |
| type Scale "BGN" "lev" Source # | |
| type Scale "BGN" "stotinka" Source # | |
| type Scale "BHD" "BHD" Source # | |
| type Scale "BHD" "dinar" Source # | |
| type Scale "BHD" "fils" Source # | |
| type Scale "BIF" "BIF" Source # | |
| type Scale "BIF" "centime" Source # | |
| type Scale "BIF" "franc" Source # | |
| type Scale "BMD" "BMD" Source # | |
| type Scale "BMD" "cent" Source # | |
| type Scale "BMD" "dollar" Source # | |
| type Scale "BND" "BND" Source # | |
| type Scale "BND" "dollar" Source # | |
| type Scale "BND" "sen" Source # | |
| type Scale "BOB" "BOB" Source # | |
| type Scale "BOB" "boliviano" Source # | |
| type Scale "BOB" "centavo" Source # | |
| type Scale "BOV" "BOV" Source # | |
| type Scale "BRL" "BRL" Source # | |
| type Scale "BRL" "centavo" Source # | |
| type Scale "BRL" "real" Source # | |
| type Scale "BSD" "BSD" Source # | |
| type Scale "BSD" "cent" Source # | |
| type Scale "BSD" "dollar" Source # | |
| type Scale "BTC" "BTC" Source # | |
| type Scale "BTC" "bitcoin" Source # | |
| type Scale "BTC" "satoshi" Source # | |
| type Scale "BTN" "BTN" Source # | |
| type Scale "BTN" "chetrum" Source # | |
| type Scale "BTN" "ngultrum" Source # | |
| type Scale "BWP" "BWP" Source # | |
| type Scale "BWP" "pula" Source # | |
| type Scale "BWP" "thebe" Source # | |
| type Scale "BYN" "BYN" Source # | |
| type Scale "BYR" "BYR" Source # | |
| type Scale "BYR" "kapyeyka" Source # | |
| type Scale "BYR" "ruble" Source # | |
| type Scale "BZD" "BZD" Source # | |
| type Scale "BZD" "cent" Source # | |
| type Scale "BZD" "dollar" Source # | |
| type Scale "CAD" "CAD" Source # | |
| type Scale "CAD" "cent" Source # | |
| type Scale "CAD" "dollar" Source # | |
| type Scale "CDF" "CDF" Source # | |
| type Scale "CDF" "centime" Source # | |
| type Scale "CDF" "franc" Source # | |
| type Scale "CHE" "CHE" Source # | |
| type Scale "CHF" "CHF" Source # | |
| type Scale "CHF" "franc" Source # | |
| type Scale "CHF" "rappen" Source # | |
| type Scale "CHW" "CHW" Source # | |
| type Scale "CLF" "CLF" Source # | |
| type Scale "CLP" "CLP" Source # | |
| type Scale "CLP" "centavo" Source # | |
| type Scale "CLP" "peso" Source # | |
| type Scale "CNY" "CNY" Source # | |
| type Scale "CNY" "fen" Source # | |
| type Scale "CNY" "yuan" Source # | |
| type Scale "COP" "COP" Source # | |
| type Scale "COP" "centavo" Source # | |
| type Scale "COP" "peso" Source # | |
| type Scale "COU" "COU" Source # | |
| type Scale "CRC" "CRC" Source # | |
| type Scale "CRC" "centimo" Source # | |
| type Scale "CRC" "colon" Source # | |
| type Scale "CUC" "CUC" Source # | |
| type Scale "CUC" "centavo" Source # | |
| type Scale "CUC" "peso" Source # | |
| type Scale "CUP" "CUP" Source # | |
| type Scale "CUP" "centavo" Source # | |
| type Scale "CUP" "peso" Source # | |
| type Scale "CVE" "CVE" Source # | |
| type Scale "CVE" "centavo" Source # | |
| type Scale "CVE" "escudo" Source # | |
| type Scale "CZK" "CZK" Source # | |
| type Scale "CZK" "haler" Source # | |
| type Scale "CZK" "koruna" Source # | |
| type Scale "DJF" "DJF" Source # | |
| type Scale "DJF" "centime" Source # | |
| type Scale "DJF" "franc" Source # | |
| type Scale "DKK" "DKK" Source # | |
| type Scale "DKK" "krone" Source # | |
| type Scale "DKK" "ore" Source # | |
| type Scale "DOP" "DOP" Source # | |
| type Scale "DOP" "centavo" Source # | |
| type Scale "DOP" "peso" Source # | |
| type Scale "DZD" "DZD" Source # | |
| type Scale "DZD" "dinar" Source # | |
| type Scale "DZD" "santeem" Source # | |
| type Scale "EGP" "EGP" Source # | |
| type Scale "EGP" "piastre" Source # | |
| type Scale "EGP" "pound" Source # | |
| type Scale "ERN" "ERN" Source # | |
| type Scale "ERN" "cent" Source # | |
| type Scale "ERN" "nafka" Source # | |
| type Scale "ETB" "ETB" Source # | |
| type Scale "ETB" "birr" Source # | |
| type Scale "ETB" "santim" Source # | |
| type Scale "ETH" "ETH" Source # | |
| type Scale "ETH" "babbage" Source # | |
| type Scale "ETH" "ether" Source # | |
| type Scale "ETH" "finney" Source # | |
| type Scale "ETH" "gwei" Source # | |
| type Scale "ETH" "kwei" Source # | |
| type Scale "ETH" "lovelace" Source # | |
| type Scale "ETH" "microether" Source # | |
| type Scale "ETH" "milliether" Source # | |
| type Scale "ETH" "mwei" Source # | |
| type Scale "ETH" "shannon" Source # | |
| type Scale "ETH" "szabo" Source # | |
| type Scale "ETH" "wei" Source # | |
| type Scale "EUR" "EUR" Source # | |
| type Scale "EUR" "cent" Source # | |
| type Scale "EUR" "euro" Source # | |
| type Scale "FJD" "FJD" Source # | |
| type Scale "FKP" "FKP" Source # | |
| type Scale "FKP" "penny" Source # | |
| type Scale "FKP" "pound" Source # | |
| type Scale "GBP" "GBP" Source # | |
| type Scale "GBP" "penny" Source # | |
| type Scale "GBP" "pound" Source # | |
| type Scale "GEL" "GEL" Source # | |
| type Scale "GEL" "lari" Source # | |
| type Scale "GEL" "tetri" Source # | |
| type Scale "GHS" "GHS" Source # | |
| type Scale "GHS" "cedi" Source # | |
| type Scale "GHS" "pesewa" Source # | |
| type Scale "GIP" "GIP" Source # | |
| type Scale "GIP" "penny" Source # | |
| type Scale "GIP" "pound" Source # | |
| type Scale "GMD" "GMD" Source # | |
| type Scale "GMD" "butut" Source # | |
| type Scale "GMD" "dalasi" Source # | |
| type Scale "GNF" "GNF" Source # | |
| type Scale "GNF" "centime" Source # | |
| type Scale "GNF" "franc" Source # | |
| type Scale "GTQ" "GTQ" Source # | |
| type Scale "GTQ" "centavo" Source # | |
| type Scale "GTQ" "quetzal" Source # | |
| type Scale "GYD" "GYD" Source # | |
| type Scale "GYD" "cent" Source # | |
| type Scale "GYD" "dollar" Source # | |
| type Scale "HKD" "HKD" Source # | |
| type Scale "HKD" "cent" Source # | |
| type Scale "HKD" "dollar" Source # | |
| type Scale "HNL" "HNL" Source # | |
| type Scale "HNL" "centavo" Source # | |
| type Scale "HNL" "lempira" Source # | |
| type Scale "HRK" "HRK" Source # | |
| type Scale "HRK" "kuna" Source # | |
| type Scale "HRK" "lipa" Source # | |
| type Scale "HTG" "HTG" Source # | |
| type Scale "HTG" "centime" Source # | |
| type Scale "HTG" "gourde" Source # | |
| type Scale "HUF" "HUF" Source # | |
| type Scale "HUF" "filler" Source # | |
| type Scale "HUF" "forint" Source # | |
| type Scale "IDR" "IDR" Source # | |
| type Scale "IDR" "rupiah" Source # | |
| type Scale "IDR" "sen" Source # | |
| type Scale "ILS" "ILS" Source # | |
| type Scale "ILS" "agora" Source # | |
| type Scale "ILS" "shekel" Source # | |
| type Scale "INR" "INR" Source # | |
| type Scale "INR" "paisa" Source # | |
| type Scale "INR" "rupee" Source # | |
| type Scale "IQD" "IQD" Source # | |
| type Scale "IQD" "dinar" Source # | |
| type Scale "IQD" "fils" Source # | |
| type Scale "IRR" "IRR" Source # | |
| type Scale "IRR" "dinar" Source # | |
| type Scale "IRR" "rial" Source # | |
| type Scale "ISK" "ISK" Source # | |
| type Scale "ISK" "eyir" Source # | |
| type Scale "ISK" "krona" Source # | |
| type Scale "JMD" "JMD" Source # | |
| type Scale "JMD" "cent" Source # | |
| type Scale "JMD" "dollar" Source # | |
| type Scale "JOD" "JOD" Source # | |
| type Scale "JOD" "dinar" Source # | |
| type Scale "JOD" "piastre" Source # | |
| type Scale "JPY" "JPY" Source # | |
| type Scale "JPY" "sen" Source # | |
| type Scale "JPY" "yen" Source # | |
| type Scale "KES" "KES" Source # | |
| type Scale "KES" "cent" Source # | |
| type Scale "KES" "shilling" Source # | |
| type Scale "KGS" "KGS" Source # | |
| type Scale "KGS" "som" Source # | |
| type Scale "KGS" "tyiyn" Source # | |
| type Scale "KHR" "KHR" Source # | |
| type Scale "KHR" "riel" Source # | |
| type Scale "KHR" "sen" Source # | |
| type Scale "KMF" "KMF" Source # | |
| type Scale "KMF" "centime" Source # | |
| type Scale "KMF" "franc" Source # | |
| type Scale "KPW" "KPW" Source # | |
| type Scale "KPW" "chon" Source # | |
| type Scale "KPW" "won" Source # | |
| type Scale "KRW" "KRW" Source # | |
| type Scale "KRW" "jeon" Source # | |
| type Scale "KRW" "won" Source # | |
| type Scale "KWD" "KWD" Source # | |
| type Scale "KWD" "dinar" Source # | |
| type Scale "KWD" "fils" Source # | |
| type Scale "KYD" "KYD" Source # | |
| type Scale "KYD" "cent" Source # | |
| type Scale "KYD" "dollar" Source # | |
| type Scale "KZT" "KZT" Source # | |
| type Scale "KZT" "tenge" Source # | |
| type Scale "KZT" "tiyin" Source # | |
| type Scale "LAK" "LAK" Source # | |
| type Scale "LAK" "att" Source # | |
| type Scale "LAK" "kip" Source # | |
| type Scale "LBP" "LBP" Source # | |
| type Scale "LBP" "piastre" Source # | |
| type Scale "LBP" "pound" Source # | |
| type Scale "LKR" "LKR" Source # | |
| type Scale "LKR" "cent" Source # | |
| type Scale "LKR" "rupee" Source # | |
| type Scale "LRD" "LRD" Source # | |
| type Scale "LRD" "cent" Source # | |
| type Scale "LRD" "dollar" Source # | |
| type Scale "LSL" "LSL" Source # | |
| type Scale "LSL" "loti" Source # | |
| type Scale "LSL" "sente" Source # | |
| type Scale "LYD" "LYD" Source # | |
| type Scale "LYD" "dinar" Source # | |
| type Scale "LYD" "dirham" Source # | |
| type Scale "MAD" "MAD" Source # | |
| type Scale "MAD" "centime" Source # | |
| type Scale "MAD" "dirham" Source # | |
| type Scale "MDL" "MDL" Source # | |
| type Scale "MDL" "ban" Source # | |
| type Scale "MDL" "leu" Source # | |
| type Scale "MGA" "MGA" Source # | |
| type Scale "MGA" "ariary" Source # | |
| type Scale "MGA" "iraimbilanja" Source # | |
| type Scale "MKD" "MKD" Source # | |
| type Scale "MKD" "denar" Source # | |
| type Scale "MKD" "deni" Source # | |
| type Scale "MMK" "MMK" Source # | |
| type Scale "MMK" "kyat" Source # | |
| type Scale "MMK" "pya" Source # | |
| type Scale "MNT" "MNT" Source # | |
| type Scale "MNT" "mongo" Source # | |
| type Scale "MNT" "tugrik" Source # | |
| type Scale "MOP" "MOP" Source # | |
| type Scale "MOP" "avo" Source # | |
| type Scale "MOP" "pataca" Source # | |
| type Scale "MRO" "MRO" Source # | |
| type Scale "MRO" "khoums" Source # | |
| type Scale "MRO" "ouguiya" Source # | |
| type Scale "MUR" "MUR" Source # | |
| type Scale "MUR" "cent" Source # | |
| type Scale "MUR" "rupee" Source # | |
| type Scale "MVR" "MVR" Source # | |
| type Scale "MVR" "laari" Source # | |
| type Scale "MVR" "rufiyaa" Source # | |
| type Scale "MWK" "MWK" Source # | |
| type Scale "MWK" "kwacha" Source # | |
| type Scale "MWK" "tambala" Source # | |
| type Scale "MXN" "MXN" Source # | |
| type Scale "MXN" "centavo" Source # | |
| type Scale "MXN" "peso" Source # | |
| type Scale "MXV" "MXV" Source # | |
| type Scale "MYR" "MYR" Source # | |
| type Scale "MYR" "ringgit" Source # | |
| type Scale "MYR" "sen" Source # | |
| type Scale "MZN" "MZN" Source # | |
| type Scale "MZN" "centavo" Source # | |
| type Scale "MZN" "metical" Source # | |
| type Scale "NAD" "NAD" Source # | |
| type Scale "NAD" "cent" Source # | |
| type Scale "NAD" "dollar" Source # | |
| type Scale "NGN" "NGN" Source # | |
| type Scale "NGN" "kobo" Source # | |
| type Scale "NGN" "naira" Source # | |
| type Scale "NIO" "NIO" Source # | |
| type Scale "NIO" "centavo" Source # | |
| type Scale "NIO" "cordoba" Source # | |
| type Scale "NOK" "NOK" Source # | |
| type Scale "NOK" "krone" Source # | |
| type Scale "NOK" "ore" Source # | |
| type Scale "NPR" "NPR" Source # | |
| type Scale "NPR" "paisa" Source # | |
| type Scale "NPR" "rupee" Source # | |
| type Scale "NZD" "NZD" Source # | |
| type Scale "NZD" "cent" Source # | |
| type Scale "NZD" "dollar" Source # | |
| type Scale "OMR" "OMR" Source # | |
| type Scale "OMR" "baisa" Source # | |
| type Scale "OMR" "rial" Source # | |
| type Scale "PAB" "PAB" Source # | |
| type Scale "PAB" "balboa" Source # | |
| type Scale "PAB" "centesimo" Source # | |
| type Scale "PEN" "PEN" Source # | |
| type Scale "PEN" "centimo" Source # | |
| type Scale "PEN" "sol" Source # | |
| type Scale "PGK" "PGK" Source # | |
| type Scale "PGK" "kina" Source # | |
| type Scale "PGK" "toea" Source # | |
| type Scale "PHP" "PHP" Source # | |
| type Scale "PHP" "centavo" Source # | |
| type Scale "PHP" "peso" Source # | |
| type Scale "PKR" "PKR" Source # | |
| type Scale "PKR" "paisa" Source # | |
| type Scale "PKR" "rupee" Source # | |
| type Scale "PLN" "PLN" Source # | |
| type Scale "PLN" "grosz" Source # | |
| type Scale "PLN" "zloty" Source # | |
| type Scale "PYG" "PYG" Source # | |
| type Scale "PYG" "centimo" Source # | |
| type Scale "PYG" "guarani" Source # | |
| type Scale "QAR" "QAR" Source # | |
| type Scale "QAR" "dirham" Source # | |
| type Scale "QAR" "riyal" Source # | |
| type Scale "RON" "RON" Source # | |
| type Scale "RON" "ban" Source # | |
| type Scale "RON" "leu" Source # | |
| type Scale "RSD" "RSD" Source # | |
| type Scale "RSD" "dinar" Source # | |
| type Scale "RSD" "para" Source # | |
| type Scale "RUB" "RUB" Source # | |
| type Scale "RUB" "kopek" Source # | |
| type Scale "RUB" "ruble" Source # | |
| type Scale "RWF" "RWF" Source # | |
| type Scale "RWF" "centime" Source # | |
| type Scale "RWF" "franc" Source # | |
| type Scale "SAR" "SAR" Source # | |
| type Scale "SAR" "halala" Source # | |
| type Scale "SAR" "riyal" Source # | |
| type Scale "SBD" "SBD" Source # | |
| type Scale "SBD" "cent" Source # | |
| type Scale "SBD" "dollar" Source # | |
| type Scale "SCR" "SCR" Source # | |
| type Scale "SCR" "cent" Source # | |
| type Scale "SCR" "rupee" Source # | |
| type Scale "SDG" "SDG" Source # | |
| type Scale "SDG" "piastre" Source # | |
| type Scale "SDG" "pound" Source # | |
| type Scale "SEK" "SEK" Source # | |
| type Scale "SEK" "krona" Source # | |
| type Scale "SEK" "ore" Source # | |
| type Scale "SGD" "SGD" Source # | |
| type Scale "SGD" "cent" Source # | |
| type Scale "SGD" "dollar" Source # | |
| type Scale "SHP" "SHP" Source # | |
| type Scale "SHP" "penny" Source # | |
| type Scale "SHP" "pound" Source # | |
| type Scale "SLL" "SLL" Source # | |
| type Scale "SLL" "cent" Source # | |
| type Scale "SLL" "leone" Source # | |
| type Scale "SOS" "SOS" Source # | |
| type Scale "SOS" "cent" Source # | |
| type Scale "SOS" "shilling" Source # | |
| type Scale "SRD" "SRD" Source # | |
| type Scale "SRD" "cent" Source # | |
| type Scale "SRD" "dollar" Source # | |
| type Scale "SSP" "SSP" Source # | |
| type Scale "SSP" "piastre" Source # | |
| type Scale "SSP" "pound" Source # | |
| type Scale "STD" "STD" Source # | |
| type Scale "STD" "centimo" Source # | |
| type Scale "STD" "dobra" Source # | |
| type Scale "SVC" "SVC" Source # | |
| type Scale "SVC" "centavo" Source # | |
| type Scale "SVC" "colon" Source # | |
| type Scale "SYP" "SYP" Source # | |
| type Scale "SYP" "piastre" Source # | |
| type Scale "SYP" "pound" Source # | |
| type Scale "SZL" "SZL" Source # | |
| type Scale "SZL" "cent" Source # | |
| type Scale "SZL" "lilangeni" Source # | |
| type Scale "THB" "THB" Source # | |
| type Scale "THB" "baht" Source # | |
| type Scale "THB" "satang" Source # | |
| type Scale "TJS" "TJS" Source # | |
| type Scale "TJS" "diram" Source # | |
| type Scale "TJS" "somoni" Source # | |
| type Scale "TMT" "TMT" Source # | |
| type Scale "TMT" "manat" Source # | |
| type Scale "TMT" "tennesi" Source # | |
| type Scale "TND" "TND" Source # | |
| type Scale "TND" "dinar" Source # | |
| type Scale "TND" "millime" Source # | |
| type Scale "TOP" "TOP" Source # | |
| type Scale "TOP" "pa'anga" Source # | |
| type Scale "TOP" "seniti" Source # | |
| type Scale "TRY" "TRY" Source # | |
| type Scale "TRY" "kurus" Source # | |
| type Scale "TRY" "lira" Source # | |
| type Scale "TTD" "TTD" Source # | |
| type Scale "TTD" "cent" Source # | |
| type Scale "TTD" "dollar" Source # | |
| type Scale "TWD" "TWD" Source # | |
| type Scale "TWD" "cent" Source # | |
| type Scale "TWD" "dollar" Source # | |
| type Scale "TZS" "TZS" Source # | |
| type Scale "TZS" "cent" Source # | |
| type Scale "TZS" "shilling" Source # | |
| type Scale "UAH" "UAH" Source # | |
| type Scale "UAH" "hryvnia" Source # | |
| type Scale "UAH" "kopiyka" Source # | |
| type Scale "UGX" "UGX" Source # | |
| type Scale "UGX" "cent" Source # | |
| type Scale "UGX" "shilling" Source # | |
| type Scale "USD" "USD" Source # | |
| type Scale "USD" "cent" Source # | |
| type Scale "USD" "dollar" Source # | |
| type Scale "USN" "USN" Source # | |
| type Scale "UYI" "UYI" Source # | |
| type Scale "UYU" "UYU" Source # | |
| type Scale "UYU" "centesimo" Source # | |
| type Scale "UYU" "peso" Source # | |
| type Scale "UZS" "UZS" Source # | |
| type Scale "UZS" "som" Source # | |
| type Scale "UZS" "tiyin" Source # | |
| type Scale "VEF" "VEF" Source # | |
| type Scale "VEF" "bolivar" Source # | |
| type Scale "VEF" "centimo" Source # | |
| type Scale "VND" "VND" Source # | |
| type Scale "VND" "dong" Source # | |
| type Scale "VND" "hao" Source # | |
| type Scale "VUV" "VUV" Source # | |
| type Scale "VUV" "vatu" Source # | |
| type Scale "WST" "WST" Source # | |
| type Scale "WST" "sene" Source # | |
| type Scale "WST" "tala" Source # | |
| type Scale "XAF" "XAF" Source # | |
| type Scale "XAF" "centime" Source # | |
| type Scale "XAF" "franc" Source # | |
| type Scale "XAG" "XAG" Source # | |
| type Scale "XAG" "grain" Source # | |
| type Scale "XAG" "gram" Source # | |
| type Scale "XAG" "kilogram" Source # | |
| type Scale "XAG" "micrograin" Source # | |
| type Scale "XAG" "microgram" Source # | |
| type Scale "XAG" "milligrain" Source # | |
| type Scale "XAG" "milligram" Source # | |
| type Scale "XAG" "troy-ounce" Source # | |
| type Scale "XAU" "XAU" Source # | |
| type Scale "XAU" "grain" Source # | |
| type Scale "XAU" "gram" Source # | |
| type Scale "XAU" "kilogram" Source # | |
| type Scale "XAU" "micrograin" Source # | |
| type Scale "XAU" "microgram" Source # | |
| type Scale "XAU" "milligrain" Source # | |
| type Scale "XAU" "milligram" Source # | |
| type Scale "XAU" "troy-ounce" Source # | |
| type Scale "XBT" "XBT" Source # | |
| type Scale "XBT" "bitcoin" Source # | |
| type Scale "XBT" "satoshi" Source # | |
| type Scale "XCD" "XCD" Source # | |
| type Scale "XCD" "cent" Source # | |
| type Scale "XCD" "dollar" Source # | |
| type Scale "XDR" "XDR" Source # | |
| type Scale "XOF" "XOF" Source # | |
| type Scale "XOF" "centime" Source # | |
| type Scale "XOF" "franc" Source # | |
| type Scale "XPD" "XPD" Source # | |
| type Scale "XPD" "grain" Source # | |
| type Scale "XPD" "gram" Source # | |
| type Scale "XPD" "kilogram" Source # | |
| type Scale "XPD" "micrograin" Source # | |
| type Scale "XPD" "microgram" Source # | |
| type Scale "XPD" "milligrain" Source # | |
| type Scale "XPD" "milligram" Source # | |
| type Scale "XPD" "troy-ounce" Source # | |
| type Scale "XPF" "XPF" Source # | |
| type Scale "XPF" "centime" Source # | |
| type Scale "XPF" "franc" Source # | |
| type Scale "XPT" "XPT" Source # | |
| type Scale "XPT" "grain" Source # | |
| type Scale "XPT" "gram" Source # | |
| type Scale "XPT" "kilogram" Source # | |
| type Scale "XPT" "micrograin" Source # | |
| type Scale "XPT" "microgram" Source # | |
| type Scale "XPT" "milligrain" Source # | |
| type Scale "XPT" "milligram" Source # | |
| type Scale "XPT" "troy-ounce" Source # | |
| type Scale "XSU" "XSU" Source # | |
| type Scale "XUA" "XUA" Source # | |
| type Scale "YER" "YER" Source # | |
| type Scale "YER" "fils" Source # | |
| type Scale "YER" "rial" Source # | |
| type Scale "ZAR" "ZAR" Source # | |
| type Scale "ZAR" "cent" Source # | |
| type Scale "ZAR" "rand" Source # | |
| type Scale "ZMW" "ZMW" Source # | |
| type Scale "ZMW" "kwacha" Source # | |
| type Scale "ZMW" "ngwee" Source # | |
| type Scale "ZWL" "ZWL" Source # | |
| type Scale "ZWL" "cent" Source # | |
| type Scale "ZWL" "dollar" Source # | |
type GoodScale scale = (CmpNat 0 (Fst scale) ~ LT, CmpNat 0 (Snd scale) ~ LT, KnownNat (Fst scale), KnownNat (Snd scale)) Source #
Currency exchange
data ExchangeRate src dst Source #
Exchange rate for converting monetary values of currency src into
monetary values of currency dst by multiplying for it.
For example, if in order to convert USD to GBP we have to multiply by 1.2345, then we can represent this situaion using:
exchangeRate(12345 % 10000) ::Maybe(ExchangeRate"USD" "GBP")
Instances
| Eq (ExchangeRate src dst) Source # | |
| Ord (ExchangeRate src dst) Source # | |
| (KnownSymbol src, KnownSymbol dst) => Read (ExchangeRate src dst) Source # | |
| (KnownSymbol src, KnownSymbol dst) => Show (ExchangeRate src dst) Source # | |
| Generic (ExchangeRate src dst) Source # | |
| Hashable (ExchangeRate src dst) Source # | |
| (KnownSymbol src, KnownSymbol dst) => ToJSON (ExchangeRate src dst) Source # | Compatible with |
| (KnownSymbol src, KnownSymbol dst) => FromJSON (ExchangeRate src dst) Source # | Compatible with |
| (KnownSymbol src, KnownSymbol dst) => Binary (ExchangeRate src dst) Source # | Compatible with |
| (KnownSymbol src, KnownSymbol dst) => Serialize (ExchangeRate src dst) Source # | Compatible with |
| NFData (ExchangeRate src dst) Source # | |
| (KnownSymbol src, KnownSymbol dst) => Store (ExchangeRate src dst) Source # | Compatible with |
| type Rep (ExchangeRate src dst) Source # | |
exchangeRate :: Rational -> Maybe (ExchangeRate src dst) Source #
Safely construct an ExchangeRate from a Rational number.
For construction to succeed, this Rational must be greater than 0,
different from infinity and different from notANumber.
fromExchangeRate :: ExchangeRate src dst -> Rational Source #
Obtain a Rational representation of the ExchangeRate.
This Rational is statically guaranteed to be greater than 0, different
from infinity and different from notANumber.
flipExchangeRate :: ExchangeRate a b -> ExchangeRate b a Source #
exchange :: ExchangeRate src dst -> Dense src -> Dense dst Source #
Apply the ExchangeRate to the given monetary value.Dense src
Identity law:
exchange(flipExchangeRatex) .exchangex ==id
Use the Identity law for reasoning about going back and forth between src
and dst in order to manage any leftovers that might not be representable as
a Discrete monetary value of src.
Serializable representations
A monomorphic representation of Dense that is easier to serialize and
deserialize than Dense in case you don't know the type indexes involved.
Instances
| Eq DenseRep Source # | |
| Ord DenseRep Source # | |
| Show DenseRep Source # | |
| Generic DenseRep Source # | |
| Hashable DenseRep Source # | |
| ToJSON DenseRep Source # | Compatible with |
| FromJSON DenseRep Source # | Compatible with |
| Binary DenseRep Source # | Compatible with |
| Serialize DenseRep Source # | Compatible with |
| NFData DenseRep Source # | |
| Store DenseRep Source # | Compatible with |
| type Rep DenseRep Source # | |
Arguments
| :: KnownSymbol currency | |
| => DenseRep | |
| -> Maybe (Dense currency) |
Arguments
| :: DenseRep | |
| -> (forall currency. KnownSymbol currency => Dense currency -> r) | |
| -> r |
Convert a DenseRep to a Dense without knowing the target currency.
Notice that currency here can't leave its intended scope unless you can
prove equality with some other type at the outer scope, but in that case you
would be better off using fromDenseRep directly.
data DiscreteRep Source #
A monomorphic representation of Discrete that is easier to serialize and
deserialize than Discrete in case you don't know the type indexes involved.
Instances
| Eq DiscreteRep Source # | |
| Ord DiscreteRep Source # | |
| Show DiscreteRep Source # | |
| Generic DiscreteRep Source # | |
| Hashable DiscreteRep Source # | |
| ToJSON DiscreteRep Source # | Compatible with |
| FromJSON DiscreteRep Source # | Compatible with |
| Binary DiscreteRep Source # | Compatible with |
| Serialize DiscreteRep Source # | Compatible with |
| NFData DiscreteRep Source # | |
| Store DiscreteRep Source # | Compatible with |
| type Rep DiscreteRep Source # | |
Arguments
| :: (KnownSymbol currency, GoodScale scale) | |
| => Discrete' currency scale | |
| -> DiscreteRep |
Convert a Discrete to a DiscreteRep for ease of serialization.
Arguments
| :: (KnownSymbol currency, GoodScale scale) | |
| => DiscreteRep | |
| -> Maybe (Discrete' currency scale) |
Attempt to convert a DiscreteRep to a Discrete, provided you know the
target currency and unit.
Arguments
| :: DiscreteRep | |
| -> (forall currency scale. (KnownSymbol currency, GoodScale scale) => Discrete' currency scale -> r) | |
| -> r |
Convert a DiscreteRep to a Discrete without knowing the target
currency and unit.
Notice that currency and unit here can't leave its intended scope unless
you can prove equality with some other type at the outer scope, but in that
case you would be better off using fromDiscreteRep directly.
Notice that you may need to add an explicit type to the result of this function in order to keep the compiler happy.
data ExchangeRateRep Source #
A monomorphic representation of ExchangeRate that is easier to serialize
and deserialize than ExchangeRate in case you don't know the type indexes
involved.
Instances
| Eq ExchangeRateRep Source # | |
| Ord ExchangeRateRep Source # | |
| Show ExchangeRateRep Source # | |
| Generic ExchangeRateRep Source # | |
| Hashable ExchangeRateRep Source # | |
| ToJSON ExchangeRateRep Source # | Compatible with |
| FromJSON ExchangeRateRep Source # | Compatible with |
| Binary ExchangeRateRep Source # | Compatible with |
| Serialize ExchangeRateRep Source # | Compatible with |
| NFData ExchangeRateRep Source # | |
| Store ExchangeRateRep Source # | Compatible with |
| type Rep ExchangeRateRep Source # | |
Arguments
| :: (KnownSymbol src, KnownSymbol dst) | |
| => ExchangeRate src dst | |
| -> ExchangeRateRep |
Convert a ExchangeRate to a DiscreteRep for ease of serialization.
Arguments
| :: (KnownSymbol src, KnownSymbol dst) | |
| => ExchangeRateRep | |
| -> Maybe (ExchangeRate src dst) |
Attempt to convert a ExchangeRateRep to a ExchangeRate, provided you
know the target src and dst types.
Arguments
| :: ExchangeRateRep | |
| -> (forall src dst. (KnownSymbol src, KnownSymbol dst) => ExchangeRate src dst -> r) | |
| -> r |
Convert a ExchangeRateRep to a ExchangeRate without knowing the target
currency and unit.
Notice that src and dst here can't leave its intended scope unless
you can prove equality with some other type at the outer scope, but in that
case you would be better off using fromExchangeRateRep directly.