Lists

The expression

list of expression

is simply syntactic sugar for

maps from {1...max(Integer)} to expression

with the understanding that the list

[`a', `a']

represents the mapping

(1, `a')
(2, `a')
(3, Undefined)

(max(Integer), Undefined)

where Undefined is a predefined value not present in any predefined type but Entity.

The above definition allows all the normal list operations to act in the expected way, provided that the length of a list $L$ is defined to be

max{all n $\in$ Integer $|$ $L$(n) $=$ Undefined}

The same syntax and conventions used to define set values can be used to define list values (but using [] instead of {}).