<html><head><meta http-equiv="Content-Type" content="text/html charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class="">I’ve had the <a href="https://github.com/lexi-lambda/racket-2htdp-typed" class="">2htdp-typed package</a> available for a little while now, which is a Typed Racket wrapper for the HtDP/2e teachpacks. It <i class="">was</i> missing big-bang, since it is implemented as a macro, but I have now added support for big-bang in Typed Racket.<div class=""><br class=""></div><div class="">The syntax of <font face="Courier" class="">big-bang</font> is identical to its untyped equivalent except for one thing: it requires an annotation that specifies what the type of the WorldState parameter should be. The exact syntax for big-bang is provided in the documentation.</div><div class=""><br class=""></div><div class="">There are still a couple of unsupported features:</div><div class=""><br class=""></div><div class=""><ul class="MailOutline"><li class="">The universe/networked worlds (“The World is Not Enough”) are not supported. This actually shouldn’t be terribly difficult to add, I just have absolutely no experience working with universe programs, so I haven’t tried.<br class=""><br class=""></li><li class="">The 2htdp/planetcute collection of sprites is not yet available in Typed Racket. This also shouldn’t be terribly difficult to add, but my first attempt ran into some complexities in how the identifiers are provided that I did not anticipate, and I haven’t taken the time to look into it since. (See <a href="https://github.com/racket/htdp/issues/2" class="">https://github.com/racket/htdp/issues/2</a> for some limited information about that.)</li></ul><div class=""><br class=""></div></div><div class="">Otherwise, I think everything should work just fine. I don’t have many programs that use these libraries sitting around, but I’d love to know if this wrapper works with existing world/universe programs.</div><div class=""><br class=""></div><div class="">Feedback and bug reports much appreciated, pull requests welcome!</div><div class=""><br class=""></div><div class="">Alexis King</div></body></html>