Announcing Raskell

Raskell is my answer to the lack of a proper Haskell development environment on my iPad. I wrote Raskell to replicate the Vim + Haskell interpreter combination I work with on my laptop. Raskell contains a port of the popular hugs Haskell interpreter as well as a custom written vi-like keyboard.

Raskell's Vi-like keyboard is not intended to be a perfect reproduction of Vi keybindings on top of the iOS virtual keyboard, it is a virtual keyboard for iOS with keybindings familiar users of Desktop Vi-like editors. It preserves Vi's core strength: the ability to navigate and edit your document without moving your fingers from the home row, which particularly important on a tablet OS, where the text view has been designed for entering text without editing it. This is common when writing emails and text messages, but inappropriate for coders, who edit and navigate code far more than they write it. This keyboard contains, of course, a subset of the functionality of Desktop Vi-like editors, such as Vim, in fact the set of commands I most commonly use. I intend to add more over time, so get in touch if your favourite is missing. There is no scripting, and none of Vi's : commands have survived as they wouldn't be appropriate here, but movement commands, delete, yank, search and multipliers are there, saving you from ever needing to use the iOS text view's selection commands again. Indent and comment keys have also been added.

An exciting aspect of this iOS translation of Vi, not possible with it's distant desktop cousins, is that with a virtual keyboard it is possible to change the markings on the keys, and so provide a cheat sheet along with the editor itself. This will disappoint those for whom Vi's incomprehensibility is it's greatest virtue, those for whom Vi's mystical keybindings are the secret knock to an elite guild of code ninjas, but for an idiot like myself this integrated cheat sheet would have made the transition to Vim much easier, and it would saved me from many years of snail-pace coding with Nano. I hope this iOS incarnation does just that for some users out there.

This editor works well for me, but I'm sure that not everyone will agree with my decisions on how best to port Vi "in spirit" to iOS, or other aspects of Raskell, so please get in touch at if you have any comments.

Posted on 29 December 2013

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