bet-0.1.2.1: Betfair API bindings. Bet on sports on betting exchanges.

Safe HaskellNone
LanguageHaskell2010

Data.Bet

Contents

Description

Data types and functions to work with odds and stakes.

Synopsis

Bets

data BetType Source

A bet type. In a betting exchange, you usually can choose if you want to make a back or lay bet. With traditional bookmakers, you usually only back.

Constructors

Back 
Lay 

Instances

oppositeBetType :: BetType -> BetType Source

Returns the opposite bet type.

betBool :: Iso' BetType Bool Source

An Iso from BetType to Bool.

data Bet odds money Source

Describes a bet in terms of its (European) odds and the stake size.

    Bet odds money = Bet BetType odds money
         ^     ^
         |     |
         |     +--- Data type of the money to use.
         |
         +-- Describes the data type used as odds.
             Some betting environments don't allow just any odds so
             it may be useful to use this type variable to restrict
             available odds.

Constructors

Bet !BetType odds money 

Instances

Bitraversable Bet 
Bifunctor Bet 
Bifoldable1 Bet 
Bifoldable Bet 
Functor (Bet odds) 
Foldable (Bet odds) 
Traversable (Bet odds) 
Foldable1 (Bet odds) 
(Eq odds, Eq money) => Eq (Bet odds money) 
(Ord odds, Ord money) => Ord (Bet odds money) 
(Read odds, Read money) => Read (Bet odds money) 
(Show odds, Show money) => Show (Bet odds money) 
(Semigroup odds, Semigroup money) => Semigroup (Bet odds money) 
Typeable (* -> * -> *) Bet 

newtype BetFlipped money odds Source

A wrapper to use odds as last type argument.

Constructors

BetFlipped 

Fields

getFlipped :: Bet odds money
 

Instances

Bitraversable BetFlipped 
Bifunctor BetFlipped 
Bifoldable1 BetFlipped 
Bifoldable BetFlipped 
Functor (BetFlipped money) 
Foldable (BetFlipped money) 
Traversable (BetFlipped money) 
Foldable1 (BetFlipped money) 
(Eq money, Eq odds) => Eq (BetFlipped money odds) 
(Ord money, Ord odds) => Ord (BetFlipped money odds) 
(Read money, Read odds) => Read (BetFlipped money odds) 
(Show money, Show odds) => Show (BetFlipped money odds) 
(Semigroup odds, Semigroup money) => Semigroup (BetFlipped money odds) 
Typeable (* -> * -> *) BetFlipped 

betType :: Lens' (Bet odds money) BetType Source

odds :: Lens (Bet odds1 money) (Bet odds2 money) odds1 odds2 Source

stake :: Lens (Bet odds money1) (Bet odds money2) money1 money2 Source

Derived lenses

The values these lenses manipulate are calculated on the fly and not stored directly. These may not necessarily follow lens laws with 100% accuracy but only because there are inaccuracies in floating point numerical values.

liability :: (Fractional odds, odds ~ money) => Lens' (Bet odds money) money Source

Liability is the amount of money you stand to lose for a bet if you lose it.

For back bets, liability equals stake. For lay bets, liability is stake multiplied by (odds-1).

An unfortunate flaw of this function: odds and money data types need to be the same.

winningPotential :: (Fractional odds, odds ~ money) => Lens' (Bet odds money) money Source

Winning potential tells you how much you could win if this bet pays.

This is profit value. If you back bet 5 dollars at odds 2.0 then your winning potential is 5 dollars. (You will have 10 dollars if you started with 5 dollars).

Pattern synonyms

pattern BetType BetType :: Bet t t Source

Match the bet type only.

pattern BetLiability BetType t money :: Num money => Bet t (Bet money money) Source

Match with liability.

pattern BetWinningPotential BetType t money :: Num money => Bet t (Bet money money) Source

Match with winning potential.

Choosing stakes

bestTradingStake :: (Fractional odds, odds ~ money) => Bet odds money -> odds -> money Source

Given a bet and opposing bet odds, calculates the ideal stake size to minimize potential loss.

This is useful in bet trading, which gives this function its name.

bestTradingStake2 :: (Fractional odds, odds ~ money) => Bet odds money -> odds -> Bet odds money Source

Same as bestTradingStake but wraps the result in a new bet.