From type/independent-routines

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sub    mkdir(IO() $path, Int() $mode = 0o777 --> IO::Path:D)

Creates a new directory; see mode for explanation and valid values for $mode. Returns the IO::Path object pointing to the newly created directory on success; fails with X::IO::Mkdir if directory cannot be created.

Also creates parent directories, as needed (similar to *nix utility mkdir with -p option); that is, mkdir "foo/bar/ber/meow" will create foo, foo/bar, and foo/bar/ber directories if they do not exist, as well as foo/bar/ber/meow.

From type/IO/Path

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method mkdir(IO::Path:D: Int() $mode = 0o777 --> IO::Path:D)

Creates a new directory, including its parent directories, as needed (similar to *nix utility mkdir with -p option). That is, mkdir "foo/bar/ber/meow" will create foo, foo/bar, and foo/bar/ber directories as well if they do not exist.

Returns the IO::Path object pointing to the newly created directory on success; fail with X::IO::Mkdir if directory cannot be created.

See also mode for explanation and valid values for $mode.