Err package:envparse

The type of errors returned by envparse's Readers. These fall into 3 categories:
  • Variables that are unset in the environment.
  • Variables whose value is empty.
  • Variables whose value cannot be parsed.
Given a variable name and an error value, try to produce a useful error message
This module contains an extensible error infrastructure. Each kind of errors gets a separate type class which encodes a Prism (roughly a getter and a constructor). The Readers, then, have the constraints for precisely the set of errors they can return.
The default error handler
Create a Reader from a simple parser function
An error handler