Special topics

This section holds a collection of topics you might find useful when developing your app-package.


The Debugging chapter covers how to use browser() (see 26.1 Debugging modules) and the IDE’s debugger console to ‘step through’ a function line-by-line. This chapter also covers how to send and view print() statements in the UI (see 26.4 Print debugging)

App data

In App data, 27.1 reactiveValues() demonstrates how we can use reactiveValues() to store and retrieve reactive values from a ‘persistent’ object in our app. 27.1.5 Testing reactiveValues() also has examples of testing modules with values from a reactiveValues() object.

27.2 session$userData gives an example of how to store persistent, non-reactive objects in your application (see also 9.3 dev data app).

Stack traces

The Stack traces chapter…

Dependency hell

The 29  Dependency hell chapter…

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