Err: Create an 'Err' Result

In matchr: Pattern Matching and Enumerated Types in R

Description

Create an Enum variant of Result used to denote that function contained an error. This allows the creation of safer functions that do not automatically stop, without using try or tryCatch.

Usage

Err(e)

Arguments

e	Object to be wrapped in the Enum variant.

Value

a list with a single value e and classes "Result} and \code{"Enum

Examples

grepl_safe <- function(pattern, x)
{
  if (!is.character(pattern)){ return(Err("'pattern' in 'grepl_safe' was not a character value.")) }
  if (!is.character(x)){ return(Err("'x' in 'grepl_safe' was not a character value.")) }
  Ok(grepl(pattern, x))
}

#grepl_safe(123, 1:5)

matchr documentation built on Sept. 9, 2021, 5:07 p.m.