Packages Required to Reproduce Reactives

Extract the set of non-base packages needed to reproduce one or more shiny::reactive objects, with duplicates removed across every reactive passed.

Use this when building a custom UI around reprex_lockfile(): it gives you the list of detected packages to present to the user for selection.

Packages are found by reading the expression held in each reactive rather than by generating its script, so every branch of an if or switch contributes. The result may therefore be a superset of the library() calls reprex_reactive() emits for the branch actually taken, on the basis that a lockfile is safer holding a package that is not needed than missing one.

Usage

reprex_packages(..., session = shiny::getDefaultReactiveDomain())

Arguments

...

One or more shiny::reactive objects to inspect. If none are supplied, every reactive registered against session by register_reactives() is used.

session

The Shiny session to read registered reactives from. Only used when ... is empty. Defaults to the current reactive domain.

Value

A character vector of unique package names. Base packages are excluded, as they require no installation.

See also

reprex_lockfile() to turn this set into an renv lockfile, and register_reactives() to record reactives from within each module.

Examples

library(shiny)

numeric_iris <- reactive(purrr::keep(iris, is.numeric))
styled_code <- reactive(styler::style_text("1 + 1"))

# Outside a running application, isolate supplies the reactive context
isolate(reprex_packages(numeric_iris, styled_code))
#> [1] "purrr"  "styler"