Indecipherable symbols that some people claim have actual meaning.

Please see the documentation for installation instructions.

## What's included?

Importing Runes introduces several new operators and one global function that correspond to common Haskell typeclasses:

### Functor

`<^>`

(pronounced "map")

### Applicative Functor

`<*>`

(pronounced "apply")`<*`

(pronounced "left sequence")`*>`

(pronounced "right sequence")`pure`

(pronounced "pure")

### Alternative

`<|>`

(pronounced "alternate")`empty`

(pronounced "empty")

### Monad

`>>-`

(pronounced "flatMap") (left associative)`-<<`

(pronounced "flatMap") (right associative)`>->`

(pronounced "Monadic compose") (left associative)`<-<`

(pronounced "Monadic compose") (right associative)

### Implementations

We also include default implementations for Optional and Array with the following type signatures:

```
// Optional+Functor:
public func <^> <T, U>(f: T -> U, x: T?) -> U?
// Optional+Applicative:
public func <*> <T, U>(f: (T -> U)?, x: T?) -> U?
public func <* <T, U>(lhs: T?, rhs: U?) -> T?
public func *> <T, U>(lhs: T?, rhs: U?) -> U?
public func pure<T>(x: T) -> T?
// Optional+Alternative:
public func <|> <T>(lhs: T?, rhs: T?) -> T?
public func empty<T>() -> T?
// Optional+Monad:
public func >>- <T, U>(x: T?, f: T -> U?) -> U?
public func -<< <T, U>(f: T -> U?, x: T?) -> U?
public func >-> <T, U, V>(f: T -> U?, g: U -> V?) -> T -> V?
public func <-< <T, U, V>(f: U -> V?, g: T -> U?) -> T -> V?
// Array+Functor:
public func <^> <T, U>(f: T -> U, x: [T]) -> [U]
// Array+Applicative:
public func <*> <T, U>(fs: [T -> U], x: [T]) -> [U]
public func <* <T, U>(lhs: [T], rhs: [U]) -> [T]
public func *> <T, U>(lhs: [T], rhs: [U]) -> [U]
public func pure<T>(x: T) -> [T]
// Array+Alternative:
public func <|> <T>(lhs: [T], rhs: [T]) -> [T]
public func empty<T>() -> [T]
// Array+Monad:
public func >>- <T, U>(x: [T], f: T -> [U]) -> [U]
public func -<< <T, U>(f: T -> [U], x: [T]) -> [U]
public func >-> <T, U, V>(f: T -> [U], g: U -> [V]) -> T -> [V]
public func <-< <T, U, V>(f: U -> [V], g: T -> [U]) -> T -> [V]
// Result+Functor:
public func <^> <T, U, E>(f: (T) -> U, a: Result<T, E>) -> Result<U, E>
// Result+Applicative:
public func <*> <T, U, E>(f: Result<(T) -> U, E>, a: Result<T, E>) -> Result<U, E>
public func <* <T, U, E>(lhs: Result<T, E>, rhs: Result<U, E>) -> Result<T, E>
public func *> <T, U, E>(lhs: Result<T, E>, rhs: Result<U, E>) -> Result<U, E>
public func pure<T, E>(_ a: T) -> Result<T, E>
// Result+Alternative:
public func <|> <T, E>(lhs: Result<T, E>, rhs: @autoclosure () -> Result<T, E>) -> Result<T, E>
// Result+Monad:
public func >>- <T, U, E>(a: Result<T, E>, f: (T) -> Result<U, E>) -> Result<U, E>
public func -<< <T, U, E>(f: (T) -> Result<U, E>, a: Result<T, E>) -> Result<U, E>
public func >-> <T, U, V, E>(f: @escaping (T) -> Result<U, E>, g: @escaping (U) -> Result<V, E>) -> (T) -> Result<V, E>
public func <-< <T, U, V, E>(f: @escaping (U) -> Result<V, E>, g: @escaping (T) -> Result<U, E>) -> (T) -> Result<V, E>
```

## Contributing

See the CONTRIBUTING document. Thank you, contributors!

## License

Runes is Copyright (c) 2015 thoughtbot, inc. It is free software, and may be redistributed under the terms specified in the LICENSE file.

## About

Runes is maintained and funded by thoughtbot, inc. The names and logos for thoughtbot are trademarks of thoughtbot, inc.

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