Haspara.Accounting.Amount

This module provides definitions for amounts used as in accounting.

For balance definition that allows "Negative Balance" phenomenon, see Balance.

Documentation

data Amount (precision :: Nat)

Data definition for amounts.

Constructors

Amount

Fields

• amountSide :: !Side
• amountValue :: !(UnsignedQuantity precision)

Instances

KnownNat precision => FromJSON (Amount precision)

FromJSON instance for Amount.

>>> :set -XDataKinds
>>> :set -XOverloadedStrings
>>> Aeson.eitherDecode "{\"side\": \"db\", \"value\": 42}" :: Either String (Amount 2)
Right (Amount {amountSide = SideDebit, amountValue = Refined 42.00})
>>> Aeson.eitherDecode "{\"side\": \"cr\", \"value\": 42}" :: Either String (Amount 2)
Right (Amount {amountSide = SideCredit, amountValue = Refined 42.00})

Defined in Haspara.Accounting.Amount

Methods

parseJSON :: Value -> Parser (Amount precision)

parseJSONList :: Value -> Parser [Amount precision]

omittedField :: Maybe (Amount precision)

KnownNat precision => ToJSON (Amount precision)

ToJSON instance for Amount.

>>> :set -XDataKinds
>>> import Haspara.Accounting.Side
>>> import Haspara.Quantity
>>> import Refined.Unsafe
>>> Aeson.encode (Amount SideDebit (unsafeRefine (mkQuantity 42 :: Quantity 2)))
"{\"side\":\"db\",\"value\":42.0}"
>>> Aeson.encode (Amount SideCredit (unsafeRefine (mkQuantity 42 :: Quantity 2)))
"{\"side\":\"cr\",\"value\":42.0}"
>>> Aeson.eitherDecode (Aeson.encode (Amount SideDebit (unsafeRefine (mkQuantity 42 :: Quantity 2)))) :: Either String (Amount 2)
Right (Amount {amountSide = SideDebit, amountValue = Refined 42.00})
>>> Aeson.eitherDecode (Aeson.encode (Amount SideCredit (unsafeRefine (mkQuantity 42 :: Quantity 2)))) :: Either String (Amount 2)
Right (Amount {amountSide = SideCredit, amountValue = Refined 42.00})

Defined in Haspara.Accounting.Amount

Methods

toJSON :: Amount precision -> Value

toEncoding :: Amount precision -> Encoding

toJSONList :: [Amount precision] -> Value

toEncodingList :: [Amount precision] -> Encoding

omitField :: Amount precision -> Bool

Generic (Amount precision)

Defined in Haspara.Accounting.Amount

Associated Types

type Rep (Amount precision) :: Type -> Type

Methods

from :: Amount precision -> Rep (Amount precision) x

to :: Rep (Amount precision) x -> Amount precision

KnownNat precision => Show (Amount precision)

Defined in Haspara.Accounting.Amount

Methods

showsPrec :: Int -> Amount precision -> ShowS

show :: Amount precision -> String

showList :: [Amount precision] -> ShowS

Eq (Amount precision)

Defined in Haspara.Accounting.Amount

Methods

(==) :: Amount precision -> Amount precision -> Bool

(/=) :: Amount precision -> Amount precision -> Bool

Ord (Amount precision)

Defined in Haspara.Accounting.Amount

Methods

compare :: Amount precision -> Amount precision -> Ordering

(<) :: Amount precision -> Amount precision -> Bool

(<=) :: Amount precision -> Amount precision -> Bool

(>) :: Amount precision -> Amount precision -> Bool

(>=) :: Amount precision -> Amount precision -> Bool

max :: Amount precision -> Amount precision -> Amount precision

min :: Amount precision -> Amount precision -> Amount precision

type Rep (Amount precision)

Defined in Haspara.Accounting.Amount

type Rep (Amount precision) = D1 ('MetaData "Amount" "Haspara.Accounting.Amount" "haspara-0.0.0.10-LGg0czPpaCuGVkbC64W22n" 'False) (C1 ('MetaCons "Amount" 'PrefixI 'True) (S1 ('MetaSel ('Just "amountSide") 'NoSourceUnpackedness 'SourceStrict 'DecidedStrict) (Rec0 Side) :*: S1 ('MetaSel ('Just "amountValue") 'NoSourceUnpackedness 'SourceStrict 'DecidedStrict) (Rec0 (UnsignedQuantity precision))))

amountDebit :: KnownNat precision => Amount precision -> Maybe (UnsignedQuantity precision)

Returns the debit value of the Amount, if any.

amountCredit :: KnownNat precision => Amount precision -> Maybe (UnsignedQuantity precision)

Returns the credit value of the Amount, if any.

amountFromValue :: KnownNat precision => AccountKind -> Quantity precision -> Amount precision

Builds the Amount for the given value for the given AccountKind.

The value concept here refers to the value of a particular economic event as in the contribution of that event to the net-worth of the entity.

This definition of the value is different than what we refer to in amountFromQuantity. In amountFromQuantity the quantity is simply reflecting the increment or decrement in a particular account of a particular AccountKind.

For example, consider getting a loan: There are two immediate events due to this exchange:

1. Inflow of cash of some quantity to an AccountKindAsset account.
2. Inflow of loan contract with some notional value of the same quantity to a 'AccountKindLiability acount.

Let's say, the notional is USD 1,000. Therefore:

1. Inflow of USD 1,000 to the cash account.
2. Inflow of a Loan Contract of USD 1,000 to the liability account.

Conventionally, the latter is reflected as follow:

>>> :set -XDataKinds
>>> import Haspara.Quantity
>>> amountFromQuantity AccountKindLiability (mkQuantity 1000 :: Quantity 2)
Amount {amountSide = SideCredit, amountValue = Refined 1000.00}

However, if the call-site is referring to values as in the net effect of the event to the net-worth of the entity, then:

>>> amountFromValue AccountKindLiability (mkQuantity (-1000) :: Quantity 2)
Amount {amountSide = SideCredit, amountValue = Refined 1000.00}

For reference, given:

>>> let valPos = mkQuantity 42 :: Quantity 2
>>> let valNeg = mkQuantity (-42) :: Quantity 2

..., let's consider following events:

We have an inflow and outflow of some assets, respectively:

>>> amountFromValue AccountKindAsset valPos
Amount {amountSide = SideDebit, amountValue = Refined 42.00}
>>> amountFromValue AccountKindAsset valNeg
Amount {amountSide = SideCredit, amountValue = Refined 42.00}

We have some decrease and increase in our liabilities, respectively:

>>> amountFromValue AccountKindLiability valPos
Amount {amountSide = SideDebit, amountValue = Refined 42.00}
>>> amountFromValue AccountKindLiability valNeg
Amount {amountSide = SideCredit, amountValue = Refined 42.00}

We have some increase and decrease in our equity, respectively:

>>> amountFromValue AccountKindEquity valPos
Amount {amountSide = SideCredit, amountValue = Refined 42.00}
>>> amountFromValue AccountKindEquity valNeg
Amount {amountSide = SideDebit, amountValue = Refined 42.00}

We have some profit and loss in our PnL, respectively:

>>> amountFromValue AccountKindRevenue valPos
Amount {amountSide = SideCredit, amountValue = Refined 42.00}
>>> amountFromValue AccountKindRevenue valNeg
Amount {amountSide = SideDebit, amountValue = Refined 42.00}

We have some decrease and increase in our expenses, respectively:

>>> amountFromValue AccountKindExpense valPos
Amount {amountSide = SideCredit, amountValue = Refined 42.00}
>>> amountFromValue AccountKindExpense valNeg
Amount {amountSide = SideDebit, amountValue = Refined 42.00}

valueFromAmount :: KnownNat precision => AccountKind -> Amount precision -> Quantity precision

Returns the value for the given Amount for the given AccountKind.

This is dual to amountFromValue.

For values of positive and negative net-effect on the net-worth of the entity, respectively:

>>> :set -XDataKinds
>>> import Haspara.Quantity
>>> let valPos = mkQuantity 42 :: Quantity 2
>>> let valNeg = mkQuantity (-42) :: Quantity 2

..., for a check function that checks if the roundtrip to a value is successful for a given AccountKind:

>>> let check = \k v -> v == valueFromAmount k (amountFromValue k v)

..., and for the list of AccountKinds.

>>> let kinds = [minBound .. maxBound] :: [AccountKind]
>>> kinds
[AccountKindAsset,AccountKindLiability,AccountKindEquity,AccountKindRevenue,AccountKindExpense]

All checks should pass:

>>> all (\k -> check k valPos && check k valNeg) kinds
True

amountFromQuantity :: KnownNat precision => AccountKind -> Quantity precision -> Amount precision

Builds the Amount value for the given account kind and quantity.

The concept of quantity here refers to the conventional concept of what it means for an Account of a given AccountKind.

For example, a loan of USD 1,000 has an increase in our liabilities. Therefore, the quantity is expected to be positive:

>>> :set -XDataKinds
>>> import Haspara.Quantity
>>> amountFromQuantity AccountKindLiability (mkQuantity 1000 :: Quantity 2)
Amount {amountSide = SideCredit, amountValue = Refined 1000.00}

Note amountFromValue function if you are rather working with values that are conceptually different than the quantity here whereby a value refers to the value of a particular economic event as in the contribution of that event to the net-worth of the entity. Therefore, above example would be reflected as follows to get the same Amount value:

>>> amountFromValue AccountKindLiability (mkQuantity (-1000) :: Quantity 2)
Amount {amountSide = SideCredit, amountValue = Refined 1000.00}

Check amountFromValue documentation for further information.

quantityFromAmount :: KnownNat precision => AccountKind -> Amount precision -> Quantity precision

Returns the quantity for the given amount.

This is dual to amountFromQuantity.