Get the value of an environment variable or throw an error if it's value is
provided multiple times (via legacy variables) or does not match the
supported values.
Returns
The value and which environment variable it's derived from or
undefined values if not found.
Get the value of an environment variable or throw an error if it's value is provided multiple times (via legacy variables) or does not match the supported values.
Returns
The value and which environment variable it's derived from or undefined values if not found.