Resource-Based Web Applications

We present an approach to write web applications in the programming languages Haskell [8] and Curry [6]. The web applications we propose are directly based on the Hypertext Transfer Protocol (HTTP) – no additional protocol on top of HTTP is necessary. Although the main ideas are not new and already applied using other programming languages, we believe that features present in modern declarative languages – especially algebraic datatypes – serve well to represent resources on the web. 1 TRANSFER OF RESOURCE REPRESENTATIONS A resource is any piece of information named by a Uniform Resource Identifier (URI). A web application provides access to internally stored information over the Internet or accesses such information provided by other web applications. Usually, (a representation of) this information is transferred using the Hypertext Transfer Protocol (HTTP) [3] – possibly employing some protocol on top of it. Note that we do not primarily consider applications running inside a web browser like [4, 7, 9].