List

The List type represents strings separated by newlines \n. It provides a familiar way of working with array-like data. However, because of the limitations of shell, you can't have discrete elements with newlines in them. You can type the List's elements by declaring a @ variable with type before it or by putting [type] after List.

my Int @ints = 1..10;
my List[Int] $ints = 1..10;
say @ints[0].WHAT #-> Int

Int

method Int( ⟶ Int)

The list in Int context returns .elems

my @a = <one two three>;
say +@a; #-> 3

at-pos

method at-pos(Int $i ⟶ Elem-Type)

at-pos is the internal method called when the a list is accessed with the postcircumfix syntax [..]. It returns data typed as the element type (Str by default).

my @list = <one two three>;
say @list.at-pos(1); #-> two
say @list[1]; #-> two

elems

method elems( ⟶ Int)

Returns the number notional elements in the list. This is equal to 0 if the list is the empty string otherwise the number of \n + 1.

join

method join(Str $sep ⟶ Str)

Returns the result of removing the \n between each line and replacing it with a new separtor.

pop

method pop( ⟶ List)

Removes a line from the end of the list

my @a = <one two three>;
@a.pop;

push

method push(Elem-Type $item ⟶ List)

Push an element onto the end of the list. If the list doesn't end in a newline one will be added before adding the new data.

my @a;
for <one two three> {
    @a.push($_);
}

set-pos

method set-pos(Int item ⟶ List)

set-pos is the internal method called which you set a list element using the postcircumfix syntax [..].

my @a = <one two three>;
@a[1] = "deux";

shift

method shift( ⟶ List)

Removes the first line from the list

my @a = <one two three>;
@a.shift;
say @a;

unshift

method unshift(Elem-Type $item ⟶ List)

Adds a line to the front of the list.

my @a = <one two three>;
@a.unshift("zero");