"The `Boolean` value of the given string representation of a 
 boolean value, or `null` if the string does not represent a 
 boolean value.
 
 Recognized values are `\"true\"`, `\"false\"`."​
​tagged("Basic types")
​deprecated("Use [[Boolean.parse]]")
​see (`function Boolean.parse`)
​shared Boolean? parseBoolean(String string) 
        => switch (string)
        case ("true") true​
        case ("false") false​
        else null;
​