Implementation of some Examples from the Reflective Programs in Tree Calculus book in Elm.
The app can be started at https://pithub.github.io/elm-tree-calculus-samples/
To load an example click on a name on the left side, for example on "and true x". On the right you'll see the initial tree for the example and below that the final reduced tree. To toggle the display of intermediate reduction steps click on the reduced tree.