source("incl/start.R") options(progressr.debug = TRUE) message("make_progression_handler() ...") my_handler <- function(symbol = "*", file = stderr(), target = "terminal", ...) { reporter <- local({ list( update = function(config, state, progression, ...) { if (state$enabled && progression$amount != 0) cat(file = file, symbol) } ) }) make_progression_handler("my_handler", reporter, ...) } h1 <- my_handler() print(h1) h2 <- my_handler(enable = FALSE) print(h2) message("make_progression_handler() ... done") source("incl/end.R")