Type.Trout

data Lit (v :: Symbol)

A literal path segment, matching paths where the next segment is equal to the value of the Symbol.

For example, the type Lit "settings" :> Lit "general" :> "reset" would match the path /settings/general/reset.

data Capture (v :: Symbol) t

Captures one segment of a path as type t. The v is a Symbol that describes the captured value.

data CaptureAll (v :: Symbol) t

Captures all remaining segments of a path, all as type t. The v is a Symbol that describes the captured value.

data Resource ms cts

A type-level description of an HTTP resource, terminating a chain of path literals, captures, and other endpoint type constructs. The ms are the methods handled by this resource. cts are the content types that this resource supports.

data Method (m :: Symbol) r

The m symbol is the HTTP method that is handled, and r is the response representation (usually some type specific to the application domain.)

data Raw (m :: Symbol)

A type-level description of a raw middleware, terminating a chain of path literals, captures, and other endpoint type constructs. The m symbol is the HTTP method that is handled.

data Sub e t

The Sub is used to create the chain of Lit, Capture, Resource, and other such type constructs that build up an endpoint type. Sub is more often used infix with the :> operator.

type LitSub (v :: Symbol) t = Sub (Lit v) t

A handy type alias for Sub (Lit v), meant to be used infix with the :/ operator. Instead of writing Lit "a" :> Lit "b" :> ..., you can write "a" :/ "b" :/ ....

data AltE a b

AltE respresents choice, i.e. that endpoint a is tried first, and if it fails, b is tried next. AltE is written infix using :<|> and is used to compose multiple endpoint types into a larger API or site. It is used to build up recursive structures, so AltE a (AltE b c) can be written a :<|> b :<|> c.

It it also used to extract information from a type, where the information has the same structure as the type. For instance, when extracting links from an AltE type, you can pattern match the result using :<|> to access the links of a and b. That also works recursively with a pattern match like a :<|> b :<|> c :<|> d.

Constructors

• AltE a b

Operator alias for Type.Trout.Sub (right-associative / precedence 5)

Operator alias for Type.Trout.LitSub (right-associative / precedence 5)

Operator alias for Type.Trout.AltE (left-associative / precedence 4)

Operator alias for Type.Trout.AltE (left-associative / precedence 4)