System.fetch_env-exclamation-mark
You're seeing just the function
fetch_env-exclamation-mark
, go back to System module for more information.
Specs
Returns the value of the given environment variable or raises if not found.
Same as get_env/1
but raises instead of returning nil
when the variable is
not set.
Examples
iex> System.fetch_env!("PORT")
"4000"
iex> System.fetch_env!("NOT_SET")
** (ArgumentError) could not fetch environment variable "NOT_SET" because it is not set