Hakyll.Core.Identifier

An identifier is a type used to uniquely identify a resource, target...

One can think of an identifier as something similar to a file path. An identifier is a path as well, with the different elements in the path separated by / characters. Examples of identifiers are:

• posts/foo.markdown

• index

• error/404

The most important difference between an Identifier and a file path is that the identifier for an item is not necesserily the file path.

For example, we could have an index identifier, generated by Hakyll. The actual file path would be index.html, but we identify it using index.

posts/foo.markdown could be an identifier of an item that is rendered to posts/foo.html. In this case, the identifier is the name of the source file of the page.

An Identifier carries the type of the value it identifies. This basically means that an Identifier (Page String) refers to a page.

It is a phantom type parameter, meaning you can safely change this if you know what you are doing. You can change the type using the castIdentifier function.

If the a type is not known, Hakyll traditionally uses Identifier ().

Documentation

data Identifier a

An identifier used to uniquely identify a value

Constructors

Identifier

Fields

identifierGroup :: Maybe String

identifierPath :: String

Instances

Typeable1 Identifier

Eq (Identifier a)

Ord (Identifier a)

Show (Identifier a)

IsString (Identifier a)

Monoid (Identifier a)

Binary (Identifier a)

Writable (Identifier a)

castIdentifier :: Identifier a -> Identifier b

Discard the phantom type parameter of an identifier

parseIdentifier :: String -> Identifier a

Parse an identifier from a string

toFilePath :: Identifier a -> FilePath

Convert an identifier to a relative FilePath

setGroup :: Maybe String -> Identifier a -> Identifier a

Set the identifier group for some identifier