In lorenzwalthert/exceptional:

knitr::opts_chunk$set(
  collapse = TRUE,
  comment = "#>",
  fig.path = "man/figures/README-"
)

Exceptional - Better exception handling for R

The goal of exceptional is to create better exception handling. This is achived by:

• providing tools for creating not just error or warning messages at the point where the exception occurs, but creating an objecto of class "exception" that contains the message that should be displayed ot the user, the nature of it (e.g. error, warning, note etc.) and other elements that can be accessed later by the user.
• allowing the user to acces information about the exception that is beyond the scope of a simple message warning() or stop() can deliver. Again, this is possible through the class "exceptional".

Example

This is a basic example:

library("exceptional")

Instead of

message("I am pretty urgent")

We could do

my_alert <- create_exception(
  create_message(default = "I am pretty urgent"), 
  nature = "warning", 
  cause = "because the weather is getting bad. Look at the clouds",
  parameter = letters[1:3],
  id = create_id("mypackage", 1)
)

my_alert
my_alert$parameter

Exceptions should have a unique id composed of the package name and a number and may be documented.

my_alert$id
my_alert$cause

We can also create different messages depending on the language setting.

f <- function() {
  msg <- create_message(default = "That's in english", de = "Deutsche Nachricht")
  create_exception(msg, nature = "error")
}
Sys.setenv(LANG = "en")
f()

Sys.setenv(LANG = "de")
f()

lorenzwalthert/exceptional documentation built on May 19, 2019, 4:10 p.m.