Show Tree of Mixed Reactive Values

To evaluate the (reactive) values, the function walks down the tree of return values and rlang::exec()s all the shiny::is.reactive()s it can find, going until it hits a non-list (is.list()) that is also not a reactive.

Usage

mixed_react_tree_app(...)

mixed_react_tree_ui(id)

mixed_react_tree_server(id, tree = shiny::reactive(NULL))

Arguments

...

Arguments passed on to module2app

ui_wrapper: A function to wrap the resulting shiny::tagList() in. Must yield a full shiny UI, such as shiny::basicPage() or shiny::bootstrapPage(). For maximum reusability of a module, avoid depending on the wrapper and only return "vanilla" UI.
module_ui,module_server: Module functions.
ui_args,server_args: Additional arguments passed to module_serverand module_ui. server_args can be shiny::reactive()s, if corresponding argument in module_server accepts it. Named reactive server_args can change while the app runs (see module2app_bare()).
options: Named options that should be passed to the runApp call (these can be any of the following: "port", "launch.browser", "host", "quiet", "display.mode" and "test.mode"). You can also specify width and height parameters which provide a hint to the embedding environment about the ideal height/width for the app.

id

The id string to be namespaced (optional).

tree

A reactive- or non-reactive value, typically a deeply nested list of reactives and non-reactive values, as passed around between modules.

Details

In the simplest case, modules accept or return a single reactive- or non-reactive value. Non-reactive returns are uncommon, but allowed. In a more complex case, modules can accept or return deeply nested lists of reactives and non-reactives, including non-reactives which contain reactives. For example, consider a module to input the contact details of an arbitrary number of people, say, a travel group.

To quickly grasp what your module accepts and returns, this module prints both the "raw", unevaluated tree and a version of the tree with all leaves evaluated. module2app() and module2app_bare() also export both trees as this text, for tests and coding agents.

Functions

mixed_react_tree_app(): Test app
mixed_react_tree_ui(): Module UI
mixed_react_tree_server(): Module Server

Changes to the Reactive Graph

Note that because this module prints all returned reactives from the tree to the UI, the reactive graph will be deeply affected. For example, these reactives might be invalidated at a different time in your use of your modules outside of this testbed.

Bugs

The display currently includes a workaround for this (likely upstream) bug: The content of reactive gets unclass()ed before display (#40).