Question: How can I manage lists in GameMaker code?

Answer

In GameMaker, managing lists is done through the use of specific functions that handle list creation, modification, and destruction. A list in GameMaker is a data structure that can store an ordered collection of values.

Here's an example on how to create a list, add some values, retrieve them, and finally clean up by deleting the list when it's no longer needed:

// Create a new list
var my_list;
my_list = ds_list_create();

// Add some values to the list
ds_list_add(my_list, "Apple");
ds_list_add(my_list, "Banana");
ds_list_add(my_list, "Cherry");

// Retrieve values from the list using accessors or ds_list_find_value()
var first_item = my_list[| 0]; // Apple
var second_item = ds_list_find_value(my_list, 1); // Banana

// You can also change the value at a specific index
my_list[| 2] = "Blueberry";

// Loop through the list items
for (var i = 0; i < ds_list_size(my_list); i++) {
    var fruit = my_list[| i];
    // Do something with fruit
}

// Once you're done with the list, make sure to free the memory
ds_list_destroy(my_list);

The above code snippet demonstrates basic operations such as creating a list (ds_list_create), adding elements to it (ds_list_add), retrieving elements (ds_list_find_value or by using the accessor [| i] where i is the index), modifying elements directly with the accessor, iterating over the list, and cleaning up memory with ds_list_destroy.

When working with lists in GameMaker, ensure that you manage memory appropriately by destroying any lists you create once you're finished with them to prevent memory leaks.