bang: Extract Result or Return
In matchr: Pattern Matching and Enumerated Types in R

Description Usage Arguments Details Value Functions Examples

Returns the value contained inside of an Result or Option Enum or returns if failure.

## S3 method for class 'Result'
!x, ...

## S3 method for class 'Option'
!x, ...

`x`	Enumerated value of type Result or Option to unwrap
`...`	objects to be passed to methods.

This is similar to unwrap for Result and Option objects. However, an Err or None variant does not cause execution to stop. Instead, the parent function immediately returns the Enum intact. Inspired by the ? operator in Rust.

an object of any class or x if failure.

!.Result: Unwrap Result if Ok, otherwise return the Err variant in the parent function.
!.Option: Unwrap Option if Some, otherwise return the None variant in the parent function.

is_big <- function(x) {
  if (x > 10) return(Ok(x))
  Err("This is small!")
}

# If 'x' is greater than 10, the value will be printed.
# Otherwise, an error is returned.
print_big <- function(x) {
  print(!is_big(x))
}