An HTTP Request.

Show Request method.

Prism' to filter GET Requests.

>>> dummyRequest ^? _GET <&> method
Just "GET"
>>> dummyRequestForm ^? _GET <&> method
Nothing

Prism' to filter for POST Requests.

>>> dummyRequest ^? _POST <&> method
Nothing
>>> dummyRequestForm ^? _POST <&> method
Just "POST"

This Traversal lets you traverse every HTTP parameter regardless of whether it's present in the query string or in the form encoded body of a POST Request. In the rare case where there are HTTP parameters in both, every parameter is still being traversed starting from the /query string/.

You might want to use param for traversing a specific parameter.

>>> let request = dummyRequestForm & query . at "name" ?~ ["hello", "out"] & form  . at "name" ?~ ["there"]
>>> foldOf params request ^? ix "name"
Just ["hello","out","there"]

An HTTP response.

Creates an 200 OK response from the given text. It automatically encodes the text to 'utf-8'. The Mime type is text/plain.

Creates an 301 Moved Permanently response with the Location corresponding to the given Url.

This is just to pure with a refined type.

This Prism' strips/prepends a prefix to the first element of a Match.

>>> pure "/hello/there" ^? prefixed "/hello/" . _head
Just "there"

>>> prefixed "/hello/" # pure "there" & view _head
"/hello/there"

If matching the entire source it previews to an empty Text. You might use exact if you are expecting this behavior.

>>> pure "hello" ^? prefixed "hello" . _head
Just ""

This also means that to review an entire source, you need to give it an empty Text.

>>> prefixed "hello" # pure mempty & view _head
"hello"

An empty Match matches to itself regardless of the pattern.

>>> preview (prefixed "hello") (review (prefixed "hello") mempty) <&> is _Empty
Just True

This Prism' strips/appends a suffix to the first value of a Match.

>>> pure "/hello/there" ^? suffixed "there" . _head
Just "/hello/"

>>> suffixed "there" # pure "/hello/" & view _head
"/hello/there"

If matching the entire source it previews to an empty Text. You might use exact if you are expecting this behavior.

>>> pure "hello" ^? suffixed "hello" . _head
Just ""

This also means that to review an entire source, you need to give it an empty Text.

>>> suffixed "hello" # pure mempty & view _head
"hello"

An empty Match matches to itself regardless of the pattern.

>>> preview (suffixed "hello") (review (suffixed "hello") mempty) <&> is _Empty
Just True

This is just an alias to only. Use this to match the entirety of the source. The source mustn't be lifted to a Match.

>>> "hello" ^? exact "hello"
Just ()

This Prism' splits/joins at the first occurrence of a boundary for the first value of a Match.

>>> pure "hello/out/there" ^? sep "/" <&> toListOf folded
Just ["out/there","hello"]

>>> sep "/" # (pure "out/there" <> pure "hello") & view _head
"hello/out/there"

Notice what happens when there is no source before or after a boundary:

>>> pure "hello/" ^? sep "/"
Just ["","hello"]
>>> (pure "hello/" <> pure "there") ^? sep "/"
Just ["","hello","there"]

>>> pure "/hello" ^? sep "/"
Just ["hello",""]
>>> (pure "/hello" <> pure "there") ^? sep "/"
Just ["hello","","there"]

When the source is identical to the boundary: >>> pure "hello" ^? sep "hello" Just []

Prism' between a Match and a target type.

An empty GET request useful for testing.

An empty POST request with an empty form encoded body useful for testing.

Empty Url useful for testing.