stop: Customized stop, gives lines-numbers if called from script
In EmilBode/EmilMisc: Miscellaneous Functions I Found Useful

Same as base::stop(), but when called from a sourced script, it also output the filename and linenumber

1	stop(..., quiet = FALSE, call. = TRUE)

`...`	arguments passed on to base::stop()
`quiet`	Useful for controlled stopping from a script.
`call.`	logical, indicating if the call should become part of the error message. Ignored if quiet = TRUE If `TRUE`, no output is printed, and a recover-function as provided in options(error=) is bypassed.