Check whether a list-type slot on an S4 object is populated

Centralises the length(x@some_slot) > 0 idiom used in several Shiny modules to decide whether optional data (contrasts, gene sets, read reports, DEXSeq results etc) is available before showing or hiding UI for it.

Usage

has_slot_data(x, slot_name)

Arguments

x

An S4 object (e.g. ExploratorySummarizedExperiment or ExploratorySummarizedExperimentList)

slot_name

Name of the slot to check

Value

output Boolean- is the slot populated?

Examples

data(airway, package = "airway")
ese <- as(airway, "ExploratorySummarizedExperiment")
eselist <- ExploratorySummarizedExperimentList(ese)
#> Creating ExploratorySummarizedExperimentList object
has_slot_data(eselist, "contrasts")
#> [1] FALSE