Using modules

In the previous section, we created a simple module with a single function in it, and used the module in a program. In this section, we will examine other methods of how Perl 6 can load the module and its functions.

There are four keywords that we are going to explore— use, need, require and import. They all are used in the context of loading modules but behave a bit differently.

Using a module assumes at least two things—first, the module file has to be found and compiled; second, the names from the module (such as subroutines or variables) should become visible to the program.

The need keyword

Theneed keyword loads a module at compile time but does not import the names from it. Loading a module also means that all the instructions within it will be executed. Also, the BEGIN block will be run. Let us add a couple of printing instructions to the module and see how it changes the output.

Here is the new module:

unit module Add;

say 'Start';

sub add($a, $b) is export {
    return...