{-# LANGUAGE StandaloneDeriving, RecordWildCards, OverloadedStrings #-}
module Hledger.Data.Amount (
amount,
nullamt,
missingamt,
num,
usd,
eur,
gbp,
per,
hrs,
at,
(@@),
amountWithCommodity,
amountCost,
amountIsZero,
amountLooksZero,
divideAmount,
multiplyAmount,
divideAmountAndPrice,
multiplyAmountAndPrice,
amountTotalPriceToUnitPrice,
amountstyle,
styleAmount,
styleAmountExceptPrecision,
showAmount,
cshowAmount,
showAmountWithZeroCommodity,
showAmountDebug,
showAmountWithoutPrice,
setAmountPrecision,
withPrecision,
setFullPrecision,
setAmountInternalPrecision,
withInternalPrecision,
setAmountDecimalPoint,
withDecimalPoint,
canonicaliseAmount,
nullmixedamt,
missingmixedamt,
mixed,
amounts,
filterMixedAmount,
filterMixedAmountByCommodity,
mapMixedAmount,
normaliseMixedAmountSquashPricesForDisplay,
normaliseMixedAmount,
unifyMixedAmount,
mixedAmountStripPrices,
mixedAmountCost,
divideMixedAmount,
multiplyMixedAmount,
divideMixedAmountAndPrice,
multiplyMixedAmountAndPrice,
averageMixedAmounts,
isNegativeAmount,
isNegativeMixedAmount,
mixedAmountIsZero,
mixedAmountLooksZero,
mixedAmountTotalPriceToUnitPrice,
styleMixedAmount,
showMixedAmount,
showMixedAmountOneLine,
showMixedAmountDebug,
showMixedAmountWithoutPrice,
showMixedAmountOneLineWithoutPrice,
showMixedAmountElided,
showMixedAmountWithZeroCommodity,
showMixedAmountWithPrecision,
setMixedAmountPrecision,
canonicaliseMixedAmount,
ltraceamount,
tests_Amount
) where
import Control.Monad (foldM)
import Data.Char (isDigit)
import Data.Decimal (decimalPlaces, normalizeDecimal, roundTo)
import Data.Function (on)
import Data.List
import qualified Data.Map as M
import Data.Map (findWithDefault)
import Data.Maybe
import qualified Data.Text as T
import Data.Word (Word8)
import Safe (lastDef, maximumMay)
import Text.Printf
import Hledger.Data.Types
import Hledger.Data.Commodity
import Hledger.Utils
deriving instance Show MarketPrice
amountstyle = AmountStyle L False (Precision 0) (Just '.') Nothing
instance Num Amount where
abs a@Amount{aquantity=q} = a{aquantity=abs q}
signum a@Amount{aquantity=q} = a{aquantity=signum q}
fromInteger i = nullamt{aquantity=fromInteger i}
negate a@Amount{aquantity=q} = a{aquantity= -q}
(+) = similarAmountsOp (+)
(-) = similarAmountsOp (-)
(*) = similarAmountsOp (*)
amount, nullamt :: Amount
amount = Amount{acommodity="", aquantity=0, aprice=Nothing, astyle=amountstyle, aismultiplier=False}
nullamt = amount
missingamt :: Amount
missingamt = amount{acommodity="AUTO"}
num n = amount{acommodity="", aquantity=n}
hrs n = amount{acommodity="h", aquantity=n, astyle=amountstyle{asprecision=Precision 2, ascommodityside=R}}
usd n = amount{acommodity="$", aquantity=roundTo 2 n, astyle=amountstyle{asprecision=Precision 2}}
eur n = amount{acommodity="€", aquantity=roundTo 2 n, astyle=amountstyle{asprecision=Precision 2}}
gbp n = amount{acommodity="£", aquantity=roundTo 2 n, astyle=amountstyle{asprecision=Precision 2}}
per n = amount{acommodity="%", aquantity=n, astyle=amountstyle{asprecision=Precision 1, ascommodityside=R, ascommodityspaced=True}}
amt `at` priceamt = amt{aprice=Just $ UnitPrice priceamt}
amt @@ priceamt = amt{aprice=Just $ TotalPrice priceamt}
similarAmountsOp :: (Quantity -> Quantity -> Quantity) -> Amount -> Amount -> Amount
similarAmountsOp op Amount{acommodity=_, aquantity=q1, astyle=AmountStyle{asprecision=p1}}
Amount{acommodity=c2, aquantity=q2, astyle=s2@AmountStyle{asprecision=p2}} =
amount{acommodity=c2, aquantity=q1 `op` q2, astyle=s2{asprecision=max p1 p2}}
amountWithCommodity :: CommoditySymbol -> Amount -> Amount
amountWithCommodity c a = a{acommodity=c, aprice=Nothing}
amountCost :: Amount -> Amount
amountCost a@Amount{aquantity=q, aprice=mp} =
case mp of
Nothing -> a
Just (UnitPrice p@Amount{aquantity=pq}) -> p{aquantity=pq * q}
Just (TotalPrice p@Amount{aquantity=pq}) -> p{aquantity=pq * signum q}
amountTotalPriceToUnitPrice :: Amount -> Amount
amountTotalPriceToUnitPrice
a@Amount{aquantity=q, aprice=Just (TotalPrice pa@Amount{aquantity=pq, astyle=ps})}
= a{aprice = Just $ UnitPrice pa{aquantity=abs (pq/q), astyle=ps{asprecision=pp}}}
where
pp = case asprecision ps of
NaturalPrecision -> NaturalPrecision
Precision p -> Precision $ if p == maxBound then maxBound else p + 1
amountTotalPriceToUnitPrice a = a
divideAmount :: Quantity -> Amount -> Amount
divideAmount n a@Amount{aquantity=q} = a{aquantity=q/n}
multiplyAmount :: Quantity -> Amount -> Amount
multiplyAmount n a@Amount{aquantity=q} = a{aquantity=q*n}
divideAmountAndPrice :: Quantity -> Amount -> Amount
divideAmountAndPrice n a@Amount{aquantity=q,aprice=p} = a{aquantity=q/n, aprice=f <$> p}
where
f (TotalPrice a) = TotalPrice $ abs $ n `divideAmount` a
f p = p
multiplyAmountAndPrice :: Quantity -> Amount -> Amount
multiplyAmountAndPrice n a@Amount{aquantity=q,aprice=p} = a{aquantity=q*n, aprice=f <$> p}
where
f (TotalPrice a) = TotalPrice $ abs $ n `multiplyAmount` a
f p = p
isNegativeAmount :: Amount -> Bool
isNegativeAmount Amount{aquantity=q} = q < 0
amountRoundedQuantity :: Amount -> Quantity
amountRoundedQuantity Amount{aquantity=q, astyle=AmountStyle{asprecision=p}} = case p of
NaturalPrecision -> q
Precision p' -> roundTo p' q
amountLooksZero :: Amount -> Bool
amountLooksZero = (0==) . amountRoundedQuantity
amountIsZero :: Amount -> Bool
amountIsZero Amount{aquantity=q} = q == 0
showAmountWithPrecision :: AmountPrecision -> Amount -> String
showAmountWithPrecision p = showAmount . setAmountPrecision p
withPrecision :: Amount -> AmountPrecision -> Amount
withPrecision = flip setAmountPrecision
setAmountPrecision :: AmountPrecision -> Amount -> Amount
setAmountPrecision p a@Amount{astyle=s} = a{astyle=s{asprecision=p}}
setFullPrecision :: Amount -> Amount
setFullPrecision a = setAmountPrecision p a
where
p = max displayprecision naturalprecision
displayprecision = asprecision $ astyle a
naturalprecision = Precision . decimalPlaces . normalizeDecimal $ aquantity a
showAmountDebug :: Amount -> String
showAmountDebug Amount{acommodity="AUTO"} = "(missing)"
showAmountDebug Amount{..} = printf "Amount {acommodity=%s, aquantity=%s, aprice=%s, astyle=%s}" (show acommodity) (show aquantity) (showAmountPriceDebug aprice) (show astyle)
showAmountWithoutPrice :: Bool -> Amount -> String
showAmountWithoutPrice c a = showamt a{aprice=Nothing}
where
showamt = if c then cshowAmount else showAmount
setAmountInternalPrecision :: Word8 -> Amount -> Amount
setAmountInternalPrecision p a@Amount{ aquantity=q, astyle=s } = a{
astyle=s{asprecision=Precision p}
,aquantity=roundTo p q
}
withInternalPrecision :: Amount -> Word8 -> Amount
withInternalPrecision = flip setAmountInternalPrecision
setAmountDecimalPoint :: Maybe Char -> Amount -> Amount
setAmountDecimalPoint mc a@Amount{ astyle=s } = a{ astyle=s{asdecimalpoint=mc} }
withDecimalPoint :: Amount -> Maybe Char -> Amount
withDecimalPoint = flip setAmountDecimalPoint
showAmountPrice :: Maybe AmountPrice -> String
showAmountPrice Nothing = ""
showAmountPrice (Just (UnitPrice pa)) = " @ " ++ showAmount pa
showAmountPrice (Just (TotalPrice pa)) = " @@ " ++ showAmount pa
showAmountPriceDebug :: Maybe AmountPrice -> String
showAmountPriceDebug Nothing = ""
showAmountPriceDebug (Just (UnitPrice pa)) = " @ " ++ showAmountDebug pa
showAmountPriceDebug (Just (TotalPrice pa)) = " @@ " ++ showAmountDebug pa
styleAmount :: M.Map CommoditySymbol AmountStyle -> Amount -> Amount
styleAmount styles a =
case M.lookup (acommodity a) styles of
Just s -> a{astyle=s}
Nothing -> a
styleAmountExceptPrecision :: M.Map CommoditySymbol AmountStyle -> Amount -> Amount
styleAmountExceptPrecision styles a@Amount{astyle=AmountStyle{asprecision=origp}} =
case M.lookup (acommodity a) styles of
Just s -> a{astyle=s{asprecision=origp}}
Nothing -> a
showAmount :: Amount -> String
showAmount = showAmountHelper False
cshowAmount :: Amount -> String
cshowAmount a =
(if isNegativeAmount a then color Dull Red else id) $
showAmountHelper False a
showAmountHelper :: Bool -> Amount -> String
showAmountHelper _ Amount{acommodity="AUTO"} = ""
showAmountHelper showzerocommodity a@Amount{acommodity=c, aprice=mp, astyle=AmountStyle{..}} =
case ascommodityside of
L -> printf "%s%s%s%s" (T.unpack c') space quantity' price
R -> printf "%s%s%s%s" quantity' space (T.unpack c') price
where
quantity = showamountquantity a
(quantity',c') | amountLooksZero a && not showzerocommodity = ("0","")
| otherwise = (quantity, quoteCommoditySymbolIfNeeded c)
space = if not (T.null c') && ascommodityspaced then " " else "" :: String
price = showAmountPrice mp
showAmountWithZeroCommodity :: Amount -> String
showAmountWithZeroCommodity = showAmountHelper True
showamountquantity :: Amount -> String
showamountquantity amt@Amount{astyle=AmountStyle{asdecimalpoint=mdec, asdigitgroups=mgrps}} =
punctuatenumber (fromMaybe '.' mdec) mgrps . show $ amountRoundedQuantity amt
punctuatenumber :: Char -> Maybe DigitGroupStyle -> String -> String
punctuatenumber dec mgrps s = sign ++ reverse (applyDigitGroupStyle mgrps (reverse int)) ++ frac''
where
(sign,num) = break isDigit s
(int,frac) = break (=='.') num
frac' = dropWhile (=='.') frac
frac'' | null frac' = ""
| otherwise = dec:frac'
applyDigitGroupStyle :: Maybe DigitGroupStyle -> String -> String
applyDigitGroupStyle Nothing s = s
applyDigitGroupStyle (Just (DigitGroups c gs)) s = addseps (repeatLast gs) s
where
addseps [] s = s
addseps (g:gs) s
| toInteger (length s) <= toInteger g = s
| otherwise = let (part,rest) = genericSplitAt g s
in part ++ c : addseps gs rest
repeatLast [] = []
repeatLast gs = init gs ++ repeat (last gs)
canonicaliseAmount :: M.Map CommoditySymbol AmountStyle -> Amount -> Amount
canonicaliseAmount styles a@Amount{acommodity=c, astyle=s} = a{astyle=s'}
where
s' = findWithDefault s c styles
instance Num MixedAmount where
fromInteger i = Mixed [fromInteger i]
negate (Mixed as) = Mixed $ map negate as
(+) (Mixed as) (Mixed bs) = normaliseMixedAmount $ Mixed $ as ++ bs
(*) = error' "error, mixed amounts do not support multiplication"
abs = error' "error, mixed amounts do not support abs"
signum = error' "error, mixed amounts do not support signum"
nullmixedamt :: MixedAmount
nullmixedamt = Mixed []
missingmixedamt :: MixedAmount
missingmixedamt = Mixed [missingamt]
mixed :: [Amount] -> MixedAmount
mixed = normaliseMixedAmount . Mixed
normaliseMixedAmount :: MixedAmount -> MixedAmount
normaliseMixedAmount = normaliseHelper False
normaliseHelper :: Bool -> MixedAmount -> MixedAmount
normaliseHelper squashprices (Mixed as)
| missingamt `elem` as = missingmixedamt
| null nonzeros = Mixed [newzero]
| otherwise = Mixed nonzeros
where
newzero = lastDef nullamt $ filter (not . T.null . acommodity) zeros
(zeros, nonzeros) = partition amountIsZero $
map sumSimilarAmountsUsingFirstPrice $
groupBy groupfn $
sortBy sortfn
as
sortfn | squashprices = compare `on` acommodity
| otherwise = compare `on` \a -> (acommodity a, aprice a)
groupfn | squashprices = (==) `on` acommodity
| otherwise = \a1 a2 -> acommodity a1 == acommodity a2 && combinableprices a1 a2
combinableprices Amount{aprice=Nothing} Amount{aprice=Nothing} = True
combinableprices Amount{aprice=Just (UnitPrice p1)} Amount{aprice=Just (UnitPrice p2)} = p1 == p2
combinableprices _ _ = False
normaliseMixedAmountSquashPricesForDisplay :: MixedAmount -> MixedAmount
normaliseMixedAmountSquashPricesForDisplay = normaliseHelper True
unifyMixedAmount :: MixedAmount -> Maybe Amount
unifyMixedAmount = foldM combine 0 . amounts
where
combine amount result
| amountIsZero amount = Just result
| amountIsZero result = Just amount
| acommodity amount == acommodity result = Just $ amount + result
| otherwise = Nothing
sumSimilarAmountsUsingFirstPrice :: [Amount] -> Amount
sumSimilarAmountsUsingFirstPrice [] = nullamt
sumSimilarAmountsUsingFirstPrice as = (sumStrict as){aprice=aprice $ head as}
amounts :: MixedAmount -> [Amount]
amounts (Mixed as) = as
filterMixedAmount :: (Amount -> Bool) -> MixedAmount -> MixedAmount
filterMixedAmount p (Mixed as) = Mixed $ filter p as
filterMixedAmountByCommodity :: CommoditySymbol -> MixedAmount -> MixedAmount
filterMixedAmountByCommodity c (Mixed as) = Mixed as'
where
as' = case filter ((==c) . acommodity) as of
[] -> [nullamt{acommodity=c}]
as'' -> [sum as'']
mapMixedAmount :: (Amount -> Amount) -> MixedAmount -> MixedAmount
mapMixedAmount f (Mixed as) = Mixed $ map f as
mixedAmountCost :: MixedAmount -> MixedAmount
mixedAmountCost (Mixed as) = Mixed $ map amountCost as
divideMixedAmount :: Quantity -> MixedAmount -> MixedAmount
divideMixedAmount n = mapMixedAmount (divideAmount n)
multiplyMixedAmount :: Quantity -> MixedAmount -> MixedAmount
multiplyMixedAmount n = mapMixedAmount (multiplyAmount n)
divideMixedAmountAndPrice :: Quantity -> MixedAmount -> MixedAmount
divideMixedAmountAndPrice n = mapMixedAmount (divideAmountAndPrice n)
multiplyMixedAmountAndPrice :: Quantity -> MixedAmount -> MixedAmount
multiplyMixedAmountAndPrice n = mapMixedAmount (multiplyAmountAndPrice n)
averageMixedAmounts :: [MixedAmount] -> MixedAmount
averageMixedAmounts [] = 0
averageMixedAmounts as = fromIntegral (length as) `divideMixedAmount` sum as
isNegativeMixedAmount :: MixedAmount -> Maybe Bool
isNegativeMixedAmount m =
case amounts $ normaliseMixedAmountSquashPricesForDisplay m of
[] -> Just False
[a] -> Just $ isNegativeAmount a
as | all isNegativeAmount as -> Just True
as | not (any isNegativeAmount as) -> Just False
_ -> Nothing
mixedAmountLooksZero :: MixedAmount -> Bool
mixedAmountLooksZero = all amountLooksZero . amounts . normaliseMixedAmountSquashPricesForDisplay
mixedAmountIsZero :: MixedAmount -> Bool
mixedAmountIsZero = all amountIsZero . amounts . normaliseMixedAmountSquashPricesForDisplay
styleMixedAmount :: M.Map CommoditySymbol AmountStyle -> MixedAmount -> MixedAmount
styleMixedAmount styles (Mixed as) = Mixed $ map (styleAmount styles) as
showMixedAmount :: MixedAmount -> String
showMixedAmount = showMixedAmountHelper False False
showMixedAmountWithZeroCommodity :: MixedAmount -> String
showMixedAmountWithZeroCommodity = showMixedAmountHelper True False
showMixedAmountOneLine :: MixedAmount -> String
showMixedAmountOneLine = showMixedAmountHelper False True
showMixedAmountHelper :: Bool -> Bool -> MixedAmount -> String
showMixedAmountHelper showzerocommodity useoneline m =
join $ map showamt $ amounts $ normaliseMixedAmountSquashPricesForDisplay m
where
join | useoneline = intercalate ", "
| otherwise = vConcatRightAligned
showamt | showzerocommodity = showAmountWithZeroCommodity
| otherwise = showAmount
ltraceamount :: String -> MixedAmount -> MixedAmount
ltraceamount s = traceWith (((s ++ ": ") ++).showMixedAmount)
setMixedAmountPrecision :: AmountPrecision -> MixedAmount -> MixedAmount
setMixedAmountPrecision p (Mixed as) = Mixed $ map (setAmountPrecision p) as
showMixedAmountWithPrecision :: AmountPrecision -> MixedAmount -> String
showMixedAmountWithPrecision p m =
vConcatRightAligned $ map (showAmountWithPrecision p) $ amounts $ normaliseMixedAmountSquashPricesForDisplay m
showMixedAmountDebug :: MixedAmount -> String
showMixedAmountDebug m | m == missingmixedamt = "(missing)"
| otherwise = printf "Mixed [%s]" as
where as = intercalate "\n " $ map showAmountDebug $ amounts m
showMixedAmountWithoutPrice :: Bool -> MixedAmount -> String
showMixedAmountWithoutPrice c m = intercalate "\n" $ map showamt as
where
Mixed as = normaliseMixedAmountSquashPricesForDisplay $ mixedAmountStripPrices m
showamt a =
(if c && isNegativeAmount a then color Dull Red else id) $
printf (printf "%%%ds" width) $ showAmountWithoutPrice c a
where
width = fromMaybe 0 . maximumMay $ map (length . showAmount) as
mixedAmountStripPrices :: MixedAmount -> MixedAmount
mixedAmountStripPrices (Mixed as) = Mixed $ map (\a -> a{aprice=Nothing}) as
showMixedAmountOneLineWithoutPrice :: Bool -> MixedAmount -> String
showMixedAmountOneLineWithoutPrice c m =
intercalate ", " $ map (showAmountWithoutPrice c) as
where
(Mixed as) = normaliseMixedAmountSquashPricesForDisplay $ stripPrices m
stripPrices (Mixed as) = Mixed $ map stripprice as where stripprice a = a{aprice=Nothing}
showMixedAmountElided :: Bool -> MixedAmount -> String
showMixedAmountElided c m = intercalate ", " $ take 2 astrs ++ elisionstr
where
astrs = map (showAmountWithoutPrice c) as
where
(Mixed as) = normaliseMixedAmountSquashPricesForDisplay $ stripPrices m
where
stripPrices (Mixed as) = Mixed $ map stripprice as
where
stripprice a = a{aprice=Nothing}
elisionstr | n > 2 = [show (n - 2) ++ " more.."]
| otherwise = []
where
n = length astrs
canonicaliseMixedAmount :: M.Map CommoditySymbol AmountStyle -> MixedAmount -> MixedAmount
canonicaliseMixedAmount styles (Mixed as) = Mixed $ map (canonicaliseAmount styles) as
mixedAmountTotalPriceToUnitPrice :: MixedAmount -> MixedAmount
mixedAmountTotalPriceToUnitPrice (Mixed as) = Mixed $ map amountTotalPriceToUnitPrice as
tests_Amount = tests "Amount" [
tests "Amount" [
test "amountCost" $ do
amountCost (eur 1) @?= eur 1
amountCost (eur 2){aprice=Just $ UnitPrice $ usd 2} @?= usd 4
amountCost (eur 1){aprice=Just $ TotalPrice $ usd 2} @?= usd 2
amountCost (eur (-1)){aprice=Just $ TotalPrice $ usd 2} @?= usd (-2)
,test "amountLooksZero" $ do
assertBool "" $ amountLooksZero amount
assertBool "" $ amountLooksZero $ usd 0
,test "negating amounts" $ do
negate (usd 1) @?= (usd 1){aquantity= -1}
let b = (usd 1){aprice=Just $ UnitPrice $ eur 2} in negate b @?= b{aquantity= -1}
,test "adding amounts without prices" $ do
(usd 1.23 + usd (-1.23)) @?= usd 0
(usd 1.23 + usd (-1.23)) @?= usd 0
(usd (-1.23) + usd (-1.23)) @?= usd (-2.46)
sum [usd 1.23,usd (-1.23),usd (-1.23),-(usd (-1.23))] @?= usd 0
asprecision (astyle $ sum [usd 1 `withPrecision` Precision 1, usd 1 `withPrecision` Precision 3]) @?= Precision 3
asprecision (astyle $ sum [usd 1 `withPrecision` Precision 3, usd 1 `withPrecision` Precision 1]) @?= Precision 3
assertBool "" $ amountLooksZero (usd 1.23 - eur 1.23)
,test "showAmount" $ do
showAmount (usd 0 + gbp 0) @?= "0"
]
,tests "MixedAmount" [
test "adding mixed amounts to zero, the commodity and amount style are preserved" $
sum (map (Mixed . (:[]))
[usd 1.25
,usd (-1) `withPrecision` Precision 3
,usd (-0.25)
])
@?= Mixed [usd 0 `withPrecision` Precision 3]
,test "adding mixed amounts with total prices" $ do
sum (map (Mixed . (:[]))
[usd 1 @@ eur 1
,usd (-2) @@ eur 1
])
@?= Mixed [usd 1 @@ eur 1
,usd (-2) @@ eur 1
]
,test "showMixedAmount" $ do
showMixedAmount (Mixed [usd 1]) @?= "$1.00"
showMixedAmount (Mixed [usd 1 `at` eur 2]) @?= "$1.00 @ €2.00"
showMixedAmount (Mixed [usd 0]) @?= "0"
showMixedAmount (Mixed []) @?= "0"
showMixedAmount missingmixedamt @?= ""
,test "showMixedAmountWithoutPrice" $ do
let a = usd 1 `at` eur 2
showMixedAmountWithoutPrice False (Mixed [a]) @?= "$1.00"
showMixedAmountWithoutPrice False (Mixed [a, -a]) @?= "0"
,tests "normaliseMixedAmount" [
test "a missing amount overrides any other amounts" $
normaliseMixedAmount (Mixed [usd 1, missingamt]) @?= missingmixedamt
,test "unpriced same-commodity amounts are combined" $
normaliseMixedAmount (Mixed [usd 0, usd 2]) @?= Mixed [usd 2]
,test "amounts with same unit price are combined" $
normaliseMixedAmount (Mixed [usd 1 `at` eur 1, usd 1 `at` eur 1]) @?= Mixed [usd 2 `at` eur 1]
,test "amounts with different unit prices are not combined" $
normaliseMixedAmount (Mixed [usd 1 `at` eur 1, usd 1 `at` eur 2]) @?= Mixed [usd 1 `at` eur 1, usd 1 `at` eur 2]
,test "amounts with total prices are not combined" $
normaliseMixedAmount (Mixed [usd 1 @@ eur 1, usd 1 @@ eur 1]) @?= Mixed [usd 1 @@ eur 1, usd 1 @@ eur 1]
]
,test "normaliseMixedAmountSquashPricesForDisplay" $ do
normaliseMixedAmountSquashPricesForDisplay (Mixed []) @?= Mixed [nullamt]
assertBool "" $ mixedAmountLooksZero $ normaliseMixedAmountSquashPricesForDisplay
(Mixed [usd 10
,usd 10 @@ eur 7
,usd (-10)
,usd (-10) @@ eur 7
])
]
]