Option

Instead of null values, SJ uses option instead. Options can be empty or have a value. They have a few special operations to make it easy to use them. They are considered a special type, an option type cannot be passed to a normal type and vice versa. For instance, 'i32' is a normal type and 'i32?' is an option type.

class(
    x : empty'i32
    y : 0
) { this }

i : empty'i32
c : empty'class
d : value(class()) 	// creates a class and changes type from 'class' to 'class?'

isEmpty(c)		// returns true
isEmpty(d)		// returns false

c?.x			// returns empty'32 because c is empty
d?.x			// returns empty'32 because d.x is empty
d?.y			// returns 0

e : c ?: class()	// if c is empty then create a new class

ifValid c {
    c.y.asString()      // you can use 'c' without the ?. because it is inside an ifValid block
} elseEmpty {
    "oh well"
}

ifValid alpha : c, beta : d { 
   // same as above, but with multiple options 
   // and they get different name inside this scope
}