None Object

The None object represents emptiness, or better still, the absence of information. On occasion, you will receive this object as an answer to a message, in case of the result being nothing. The most essential question you could ask the None object is: None?. The answer will always read True.

Out write: None None?.

result:

True

Any object other than None will reply with False. The above code fragment may seem a bit philosophical, yet the None object certainly has extremely practical applications. For example, you will receive the None object as an answer in case you ask for a list element that does not exist. You could also use the None object if you like to declare a variable, but do not want to specify a value yet. Instead, you just assign the special value None. In Xoscript it is not allowed to declare a variable without value, such as:

>> value.

Instead, you have to write the following:

>> value := None.

[ None ] None?

Example:

>> x := None.
Out write: x None?, stop.

Result:

True

[ None ] string

Example:

>> x := None.
Out write: x string, stop.

Result:

None

[ None ] else: [ Object ]

Example:

>> x := None.
Out write: (x else: 123), stop.

Result:

123

[ None ] number

Example:

>> x := None.
Out write: x number, stop.

Result:

0

[ None ] boolean

Example:

>> x := None.
Out write: x bool, stop.

Result:

False