Course of Raku / Advanced / Debugging with dd

Dumping variables

Call dd to see the value and the type of a variable as you would do with say:

my $var = 42;
dd $var;

This code prints not only the value of the variable, but also the type of the value:

Int $var = 42

It is also possible to dump more complex data structures such as array or hashes:

my @arr = 10, 20, [1, 2, 3], 30;
dd @arr;
# Array @arr = [10, 20, [1, 2, 3], 30]

Notice that the nested array is also clearly visible.

my %hash =
    alpha => 'a',
    beta  => 'b';
dd %hash;
# Hash %hash = {:alpha("a"), :beta("b")}