Recently a very nice Haskell course on Future Learn has finished. It has been created at the University of Glasgow - the virtual birthplace of the Haskell language, where many of its original developers worked.
In this post, I will add the support for generating expressions to the Haskell, WebSockets and D3.js codebase. The users will submit expressions such as evendistr 20 [0..100] 100 times every 500ms; our task is to parse the expressions, and then to construct generator that will produce the requested values.
This is the first in the series of posts where I will explore a simple application that allows you to analyse and present data in interesting ways. I will be writing a nice AngularJS client, with the WebSocket connection to the Haskell back-end.
Let's expand our random Person generator to include keep track of the count of people generated and to write out some values during the generating process. For motivation, let's say we want to see not just the list of Persons, but also keep track of some tracing messages, and to see some sequence number while we are generating.
During the last months, we embarked in a journey deep into the Haskell lands, writing a complete web application from the ground up. In this last episode of "The Pragmatic Haskeller", we finally wire everything together to have an usable application.
after a small break let's resume our journey into the pragmatic world of the "Pragmatic Haskeller" series, this time exploring Parsec, a combinators library which will allow us to write a domain specific language to describe recipes.