WithDefaultBool returns the boolean value of the supplied environment variable or, if not present, the supplied default value.

WithDefaultDuration returns the duration value of the supplied environment variable or, if not present, the supplied default value.

WithDefaultFloat64 returns the float64 value of the supplied environment variable or, if not present, the supplied default value.

WithDefaultInt returns the int value of the supplied environment variable or, if not present, the supplied default value.

WithDefaultInt64 returns the int value of the supplied environment variable or, if not present, the supplied default value.

WithDefaultString returns the string value of the supplied environment variable or, if not present, the supplied default value.