Documentation for routine unshift assembled from the following pages:

Class: Any §

From Any

(Any) method unshift §

Defined as:

multi method unshift(Any:U: --> Array)
multi method unshift(Any:U: @values --> Array)

Initializes Any variable as empty Array and calls Array.unshift on it.

my $a;
say $a.unshift; # OUTPUT: «[]␤» 
say $a;         # OUTPUT: «[]␤» 
my $b;
say $b.unshift([1,2,3]); # OUTPUT: «[[1 2 3]]␤»

Class: Nil §

From Nil

(Nil) method unshift §

method unshift(*@)

Warns the user that they tried to unshift onto a Nil or derived type object.

Role: Buf §

From Buf

(Buf) method unshift §

method unshift()

Adds elements at the beginning of the buffer

$bú.unshift( 0 );
say $bú.raku; # OUTPUT: «Buf.new(0,1,1,2,3,5,8,13,21,34,55,89)» 

Class: Array §

From Array

(Array) routine unshift §

Defined as:

multi sub    unshift(Array:D, **@values --> Array:D)
multi method unshift(Array:D: **@values --> Array:D)

Adds the @values to the start of the array, and returns the modified array. Fails if @values is a lazy list.

Example:

my @foo = <a b c>;
@foo.unshift: 1, 3 ... 11;
say @foo;                   # OUTPUT: «[(1 3 5 7 9 11) a b c]␤»

The notes in the documentation for method push apply, regarding how many elements are added to the array.

The routine prepend is the equivalent for adding multiple elements from one list or array.