Proxy -is:module

Proxy is a type that holds no data, but has a phantom parameter of arbitrary type (or even kind). Its use is to provide type information, even though there is no value available of that type (or it may be too costly to create one). Historically, Proxy :: Proxy a is a safer alternative to the undefined :: a idiom.

>>> Proxy :: Proxy (Void, Int -> Int)
Proxy

Proxy can even hold types of higher kinds,

>>> Proxy :: Proxy Either
Proxy

>>> Proxy :: Proxy Functor
Proxy

>>> Proxy :: Proxy complicatedStructure
Proxy

Define a HTTP proxy, consisting of a hostname and port number.

Define a HTTP proxy, consisting of a hostname and port number.

HTTP proxies (or not) are represented via Proxy, specifying if a proxy should be used for the request (see setProxy)

Use the proxy given. Should be of the form "http://host:port", "host", "host:port", or "http://host". Additionally, an optional Authority for authentication with the proxy.

A Proxy is a monad transformer that receives and sends information on both an upstream and downstream interface. The type variables signify:

• a' and a - The upstream interface, where (a')s go out and (a)s come in
• b' and b - The downstream interface, where (b)s go out and (b')s come in
• m - The base monad
• r - The return value

Proxy is a type that holds no data, but has a phantom parameter of arbitrary type (or even kind). Its use is to provide type information, even though there is no value available of that type (or it may be too costly to create one). Historically, Proxy :: Proxy a is a safer alternative to the undefined :: a idiom.

>>> Proxy :: Proxy (Void, Int -> Int)
Proxy

Proxy can even hold types of higher kinds,

>>> Proxy :: Proxy Either
Proxy

>>> Proxy :: Proxy Functor
Proxy

>>> Proxy :: Proxy complicatedStructure
Proxy

Memory-managed wrapper type.

Contains no actual data, but is needed to help select the correct instance of Predicate

Proxy is a type that holds no data, but has a phantom parameter of arbitrary type (or even kind). Its use is to provide type information, even though there is no value available of that type (or it may be too costly to create one). Historically, Proxy :: Proxy a is a safer alternative to the 'undefined :: a' idiom.

>>> Proxy :: Proxy (Void, Int -> Int)
Proxy

Proxy can even hold types of higher kinds,

>>> Proxy :: Proxy Either
Proxy

>>> Proxy :: Proxy Functor
Proxy

>>> Proxy :: Proxy complicatedStructure
Proxy

A concrete, poly-kinded proxy type

spec

Optional HTTP proxy. Since 0.1.0

Convert from a Tagged representation to a representation based on a Proxy.

A lens onto proxy configuration. Example:

let opts = defaults & proxy ?~ httpProxy "localhost" 8000
getWith opts "http://httpbin.org/get"

Note here the use of the ?~ setter to turn a Proxy into a Maybe Proxy, to make the type of the RHS compatible with the proxy lens.