Option (FSharpx.Extras)

Option Module

Namespace: FSharpx
Assembly: FSharpx.Extras.dll

Types

Type	Description
MaybeBuilder	The maybe monad. This monad is my own and uses an 'T option. Others generally make their own Maybe<'T> type from Option<'T>. The builder approach is from Matthew Podwysocki's excellent Creating Extended Builders series http://codebetter.com/blogs/matthew.podwysocki/archive/2010/01/18/much-ado-about-monads-creating-extended-builders.aspx.

Functions and values

Function or value	Description
`x > y` Full Usage: `x > y` Parameters: x : `'a option` y : `'b option` Returns: `'b option` Modifiers: inline	Sequence actions, discarding the value of the first argument. x : `'a option` y : `'b option` Returns: `'b option`
`x <* y` Full Usage: `x <* y` Parameters: x : `'a option` y : `'b option` Returns: `'a option` Modifiers: inline	Sequence actions, discarding the value of the second argument. x : `'a option` y : `'b option` Returns: `'a option`
`f <!> m` Full Usage: `f <!> m` Parameters: f : `'a -> 'b` m : `'a option` Returns: `'b option` Modifiers: inline	Infix map f : `'a -> 'b` m : `'a option` Returns: `'b option`
`f <> m` Full Usage: `f <> m` Parameters: f : `('a -> 'b) option` m : `'a option` Returns: `'b option` Modifiers: inline	Sequential application f : `('a -> 'b) option` m : `'a option` Returns: `'b option`
`<=<x` Full Usage: `<=<x` Parameters: x : `'a -> 'b option` Returns: `('c -> 'a option) -> 'c -> 'b option` Modifiers: inline	Right-to-left Kleisli composition x : `'a -> 'b option` Returns: `('c -> 'a option) -> 'c -> 'b option`
`f =<< m` Full Usage: `f =<< m` Parameters: f : `'a -> 'b option` m : `'a option` Returns: `'b option` Modifiers: inline	Flipped >>= f : `'a -> 'b option` m : `'a option` Returns: `'b option`
`(>=>) f g x` Full Usage: `(>=>) f g x` Parameters: f : `'a -> 'b option` g : `'b -> 'c option` x : `'a` Returns: `'c option` Modifiers: inline	Left-to-right Kleisli composition f : `'a -> 'b option` g : `'b -> 'c option` x : `'a` Returns: `'c option`
`m >>. f` Full Usage: `m >>. f` Parameters: m : `'a option` f : `'b option` Returns: `'b option` Modifiers: inline	Sequentially compose two maybe actions, discarding any value produced by the first m : `'a option` f : `'b option` Returns: `'b option`
`m >>= f` Full Usage: `m >>= f` Parameters: m : `'a option` f : `'a -> 'b option` Returns: `'b option` Modifiers: inline	Sequentially compose two actions, passing any value produced by the first as an argument to the second. m : `'a option` f : `'a -> 'b option` Returns: `'b option`
`ap m f` Full Usage: `ap m f` Parameters: m : `'a option` f : `('a -> 'b) option` Returns: `'b option` Modifiers: inline	Sequential application m : `'a option` f : `('a -> 'b) option` Returns: `'b option`
`cast o` Full Usage: `cast o` Parameters: o : `obj` Returns: `'a option` Modifiers: inline	Attempts to cast an object. Returns None if unsuccessful. o : `obj` Returns: `'a option`
`concat x` Full Usage: `concat x` Parameters: x : `'a option option` Returns: `'a option` Modifiers: inline	Concatenates an option of option. x : `'a option option` Returns: `'a option`
`filter pred _arg1` Full Usage: `filter pred _arg1` Parameters: pred : `'b -> bool` _arg1 : `'b option` Returns: `'b option` Modifiers: inline Type parameters: 'b	Applies a predicate to the option. If the predicate returns true, returns Some x, otherwise None. pred : `'b -> bool` _arg1 : `'b option` Returns: `'b option`
`foldM f s` Full Usage: `foldM f s` Parameters: f : `'a -> 'b -> 'a option` s : `'a` Returns: `'b seq -> 'a option`	f : `'a -> 'b -> 'a option` s : `'a` Returns: `'b seq -> 'a option`
`fromTryPattern tryFun input` Full Usage: `fromTryPattern tryFun input` Parameters: tryFun : `'input -> bool * 'output` input : `'input` Returns: `'output option`	transforms a function in the Try...(input, out output) style into a function of type: input -> output Option Example: fromTryPattern(System.Double.TryParse) See Examples.Option tryFun : `'input -> bool * 'output` input : `'input` Returns: `'output option`
`getOrDefault _arg1` Full Usage: `getOrDefault _arg1` Parameters: _arg1 : `'a option` Returns: `'a`	Gets the value associated with the option or the default value for the type. _arg1 : `'a option` Returns: `'a`
`getOrElse v _arg1` Full Usage: `getOrElse v _arg1` Parameters: v : `'a` _arg1 : `'a option` Returns: `'a` Modifiers: inline	Gets the value associated with the option or the supplied default value. v : `'a` _arg1 : `'a option` Returns: `'a`
`getOrElseF v _arg1` Full Usage: `getOrElseF v _arg1` Parameters: v : `unit -> 'a` _arg1 : `'a option` Returns: `'a` Modifiers: inline	Gets the value associated with the option or the supplied default value from a function. v : `unit -> 'a` _arg1 : `'a option` Returns: `'a`
`getOrElseLazy v _arg1` Full Usage: `getOrElseLazy v _arg1` Parameters: v : `Lazy<'a>` _arg1 : `'a option` Returns: `'a` Modifiers: inline	Gets the value associated with the option or the supplied default value. v : `Lazy<'a>` _arg1 : `'a option` Returns: `'a`
`getOrElseWith v f _arg1` Full Usage: `getOrElseWith v f _arg1` Parameters: v : `'a` f : `'b -> 'a` _arg1 : `'b option` Returns: `'a` Modifiers: inline	v : `'a` f : `'b -> 'a` _arg1 : `'b option` Returns: `'a`
`getOrFail m _arg1` Full Usage: `getOrFail m _arg1` Parameters: m : `string` _arg1 : `'a option` Returns: `'a` Modifiers: inline	Gets the value associated with the option or fails with the supplied message. m : `string` _arg1 : `'a option` Returns: `'a`
`getOrRaise e _arg1` Full Usage: `getOrRaise e _arg1` Parameters: e : `Exception` _arg1 : `'a option` Returns: `'a` Modifiers: inline	Gets the value associated with the option or raises the supplied exception. e : `Exception` _arg1 : `'a option` Returns: `'a`
`getOrReraise e _arg1` Full Usage: `getOrReraise e _arg1` Parameters: e : `exn` _arg1 : `'a option` Returns: `'a` Modifiers: inline	Gets the value associated with the option or reraises the supplied exception. e : `exn` _arg1 : `'a option` Returns: `'a`
`isNone o` Full Usage: `isNone o` Parameters: o : `Option<'a>` Returns: `bool` Modifiers: inline Type parameters: 'a	o : `Option<'a>` Returns: `bool`
`isSome o` Full Usage: `isSome o` Parameters: o : `Option<'a>` Returns: `bool` Modifiers: inline Type parameters: 'a	o : `Option<'a>` Returns: `bool`
`lift2 f a b` Full Usage: `lift2 f a b` Parameters: f : `'d -> 'e -> 'f` a : `'d option` b : `'e option` Returns: `'f option` Modifiers: inline Type parameters: 'd, 'e, 'f	Promote a function to a monad/applicative, scanning the monadic/applicative arguments from left to right. f : `'d -> 'e -> 'f` a : `'d option` b : `'e option` Returns: `'f option`
`mapM f x` Full Usage: `mapM f x` Parameters: f : `'a -> 'b option` x : `'a list` Returns: `'b list option` Modifiers: inline	f : `'a -> 'b option` x : `'a list` Returns: `'b list option`
`maybe` Full Usage: `maybe` Returns: `MaybeBuilder`	Returns: `MaybeBuilder`
`monoid m` Full Usage: `monoid m` Parameters: m : `ISemigroup<'a>` Returns: `Monoid<'a option>`	Option wrapper monoid m : `ISemigroup<'a>` Returns: `Monoid<'a option>`
`ofBool b` Full Usage: `ofBool b` Parameters: b : `bool` Returns: `unit option` Modifiers: inline	True -> Some(), False -> None b : `bool` Returns: `unit option`
`ofBoolAndValue (arg1, arg2)` Full Usage: `ofBoolAndValue (arg1, arg2)` Parameters: arg0 : `bool` arg1 : `'a` Returns: `'a option` Modifiers: inline	If true,value then returns Some value. Otherwise returns None. Useful to process TryXX style functions. arg0 : `bool` arg1 : `'a` Returns: `'a option`
`ofChoice _arg1` Full Usage: `ofChoice _arg1` Parameters: _arg1 : `Choice<'c, 'd>` Returns: `'c option`	Maps Choice 1Of2 to Some value, otherwise None. _arg1 : `Choice<'c, 'd>` Returns: `'c option`
`ofNullable n` Full Usage: `ofNullable n` Parameters: n : `Nullable<'a>` Returns: `'a option`	Maps a Nullable to Option n : `Nullable<'a>` Returns: `'a option`
`ofResult _arg1` Full Usage: `ofResult _arg1` Parameters: _arg1 : `Result<'c, 'd>` Returns: `'c option`	Maps Result Ok to Some value, otherwise None. _arg1 : `Result<'c, 'd>` Returns: `'c option`
`ofUnchecked x` Full Usage: `ofUnchecked x` Parameters: x : `'a` Returns: `'a option` Modifiers: inline Type parameters: 'a	Maps Unchecked object when null to None, otherwise Some value. It's useful when getting data from external sources, pe. x : `'a` Returns: `'a option`
`option defaultValue map _arg1` Full Usage: `option defaultValue map _arg1` Parameters: defaultValue : `'U` map : `'T -> 'U` _arg1 : `'T option` Returns: `'U`	Haskell-style maybe operator defaultValue : `'U` map : `'T -> 'U` _arg1 : `'T option` Returns: `'U`
`orElse v _arg1` Full Usage: `orElse v _arg1` Parameters: v : `'a option` _arg1 : `'a option` Returns: `'a option` Modifiers: inline	Gets the option if Some x, otherwise the supplied default value. v : `'a option` _arg1 : `'a option` Returns: `'a option`
`orElseLazy v _arg1` Full Usage: `orElseLazy v _arg1` Parameters: v : `Lazy<'a option>` _arg1 : `'a option` Returns: `'a option` Modifiers: inline	v : `Lazy<'a option>` _arg1 : `'a option` Returns: `'a option`
`returnM x` Full Usage: `returnM x` Parameters: x : `'a` Returns: `'a option` Modifiers: inline	Inject a value into the option type x : `'a` Returns: `'a option`
`sequence s` Full Usage: `sequence s` Parameters: s : `'b option list` Returns: `'b list option` Modifiers: inline Type parameters: 'b	s : `'b option list` Returns: `'b list option`
`someIf condition x` Full Usage: `someIf condition x` Parameters: condition : `'a -> bool` x : `'a` Returns: `'a option`	Checks condition on x - if true returns Some x else None condition : `'a -> bool` x : `'a` Returns: `'a option`
`toNullable _arg1` Full Usage: `toNullable _arg1` Parameters: _arg1 : `'a option` Returns: `Nullable<'a>`	Maps an Option to Nullable _arg1 : `'a option` Returns: `Nullable<'a>`
`tryParseWith func` Full Usage: `tryParseWith func` Parameters: func : `'a -> bool * 'b` Returns: `'a -> 'b option` Modifiers: inline	Converts a function returning bool,value to a function returning value option. Useful to process TryXX style functions. func : `'a -> bool * 'b` Returns: `'a -> 'b option`