Documentation for method AT-POS assembled from the following pages:

Language documentation: Subscripts §

From Subscripts

(Subscripts) method AT-POS §

multi method AT-POS (::?CLASS:D: $index)

Expected to return the element at position $index. This is what postcircumfix [ ] normally calls.

If you want an element to be mutable (like they are for the built-in Array type), you'll have to make sure to return it in the form of an item container that evaluates to the element's value when read, and updates it when assigned to. Remember to use return-rw or the is rw routine trait to make that work; see the example.

Role: Positional §

From Positional

(Positional) method AT-POS §

method AT-POS(\position)

Should return the value / container at the given position.

Role: Sequence §

From Sequence

(Sequence) method AT-POS §

multi method AT-POS(::?CLASS:D: Int:D $idx)
multi method AT-POS(::?CLASS:D: int $idx)

Returns the element at position $idx in the cached sequence.

Class: Range §

From Range

(Range) method AT-POS §

Defined as

multi method AT-POS(Range:D: int \pos)
multi method AT-POS(Range:D: int:D \pos)

Checks if the Int position exists and in that case returns the element in that position.

say (1..4).AT-POS(2) # OUTPUT: «3␤»