Notes.md

Lookup tables pattern

Lookup tables try to emulate Java's HashTable or Python dictionary.

All we need is to create an enum for the mapping and a static array for elements of any type. Lookup tables work also with struct.

Example:

enum foo {
    foo_2 = 0,
    foo_3,
    foo_4
};

static int squares[] = {
    9,
    4,
    16
}

Then, if we try to access squares' fields with foo's value, we obtain corresponding values.
However, since it is not really useful and readable, it is possible to use this syntax:

static int squares[] = {
    [foo_3] = 9,
    [foo_2] = 4,
    [foo_4] = 16
}

We can assign each element to a specific identifier and with a custom order.

Tip

In the last example enum is no longer necessary. To build cleaner lookup tables, it is advised to avoid enum.

Dimensions

Be careful about the dimension of identifiers because they may occupy a lot of memory in case they are too big. A good practice is to make them not larger than 1 byte.

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