28 lines
698 B
Haskell
28 lines
698 B
Haskell
module Currency
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where
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import Utils
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import Types
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currencies =
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[
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Currency "$" 1
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,Currency "EUR" 0.760383
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,Currency "£" 0.512527
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,Currency "h" 60 -- hours
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,Currency "m" 1 -- minutes
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]
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getcurrency :: String -> Currency
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getcurrency s = head $ [(Currency symbol rate) | (Currency symbol rate) <- currencies, symbol==s]
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conversionRate :: Currency -> Currency -> Double
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conversionRate oldc newc = (rate newc) / (rate oldc)
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-- convenient amount constructors
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dollars = Amount $ getcurrency "$"
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euro = Amount $ getcurrency "EUR"
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pounds = Amount $ getcurrency "£"
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hours = Amount $ getcurrency "h"
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minutes = Amount $ getcurrency "m"
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