Implement `mapfile` as builtin
Unlike associated arrays, these should be stored in vectors, and empty lines should be skipped.
See here how it works: https://origin.geeksforgeeks.org/mapfile-command-in-linux-with-examples/
Unlike associated arrays, these should be stored in vectors, and empty lines should be skipped.
See here how it works: https://origin.geeksforgeeks.org/mapfile-command-in-linux-with-examples/