traceInvalidation: Print the call stack that caused invalidation
In glin/reactlog: Easier Debugging with the Shiny Reactive Log

Description Usage Arguments Value See Also Examples

View source: R/trace-invalidation.R

Prints the call stack that caused a reactive context to be invalidated. The most recent call is printed first.

1 2	traceInvalidation(x = getCurrentContext(), graph = getReactGraph(), n = 1, value = TRUE, quiet = FALSE, file = "", append = FALSE)

`x`	A reactive context, expression, observer. Defaults to the current reactive context.
`graph`	A reactive graph. Defaults to the reactive graph for the current Shiny session.
`n`	Number of invalidations to trace back. Defaults to 1, the most recent invalidation.
`value`	If `TRUE`, show changed values of reactive values.
`quiet`	If `TRUE`, suppress output.
`file`	A filename or connection to print to. Defaults to `stdout`.
`append`	If `TRUE`, output will be appended to `file`.

A list (stack) of reactive graph nodes.

listDependencies()

library(shiny)
options(shiny.reactlog = TRUE)

val <- reactiveVal(1, label = "val")

rx <- reactive({
  val()
})

observe({
  traceInvalidation()
  rx()
})

observe(val(10))

# trigger flush event (happens automatically in a Shiny app)
shiny:::flushReact()

traceInvalidation(rx)