Query the Names of the Current Internal Top-Level Task Callbacks

Description

This provides a way to get the names (or identifiers)for the currently registered task callbacksthat are invoked at the conclusion of each top-level task.These identifiers can be used to remove a callback.

Usage

getTaskCallbackNames()

Value

A character vector giving the name for each of theregistered callbacks which are invoked whena top-level task is completed successfully.Each name is the one used when registeringthe callbacks and returned as the in thecall toaddTaskCallback.

Note

One can usetaskCallbackManagerto manage user-level task callbacks,i.e., S-language functions, entirely withinthe S language and access the namesmore directly.

See Also

addTaskCallback,removeTaskCallback,taskCallbackManager\https://developer.r-project.org/TaskHandlers.pdf

Examples

 n <- addTaskCallback(function(expr, value, ok, visible) {                        cat("In handler\n")                        return(TRUE)                      }, name = "simpleHandler") getTaskCallbackNames()   # now remove it by name removeTaskCallback("simpleHandler") h <- taskCallbackManager() h$add(function(expr, value, ok, visible) {                        cat("In handler\n")                        return(TRUE)                      }, name = "simpleHandler") getTaskCallbackNames() removeTaskCallback("R-taskCallbackManager")