GameMaker - multi-dimensional arrays

As you may know, GameMaker natively supports only 2-dimensional arrays with size up to 32000x32000.
However, in some cases, you may want to use arrays with 3 (or more) dimensions.
Small comparison table with descriptions below:

Stat\Method	array:offset	array:instance	ds_grid's	ds_map
Init (fill-up)	Slow	Slow	Fast	Slowest
Access (i/o)	Fast	Fast	Average	Average
Size limit	~109 cells	32k/dimension	Resizable	No
Index	Integer	Integer	Integer	String
Existance check	No	No	Not needed	Yes
Region operations	No	No	Yes	Only clearing
References	No	Partial (layer)	Yes	Yes

GameMaker - INI without an *.ini

So, say, you would like to load data from INI without creating an *.ini file somewhere.
There can be many reasons for doing so, be that security, performance, or simple fact of INI contents being defined inside of game's code.

There are two things to do about it - deciding on presentation of data, and creating a algorithm to load it. Presentation of data is relatively simple with INI - file is split into named sections, which contain named values. Since both use string index, using ds_map (sections) with other ds_map's inside (values) seems like an approriate choice. Below is my implementation.