12.14 Array How-to

12.14.1 Adding items to a multidimensional array.

The following bidimensional array stores informations about site sections. There are three sections, each identified by a label and a more descriptive string:

sections [ ] = {
    { "about", "About Us" },
    { "docs", "Documentation" },
    { "download", "Download our Software" }
};

Now, if you want to add a new section you may be tempted to do something like:

section [ ] += { "faq", "Frequently Asked Questions" };

This wouldn't lead to an array made of 4 items, each of them consisting in a 2 element array as expected. On the contrary, this is what you get:

{
    { "about", "About Us" },
    { "docs", "Documentation" },
    { "download", "Download our Software" },
    "faq",
    "Frequently Asked Questions"
};

Two string elements have been added, not a array of two strings. The right way to achieve our goals is:

sections [] += { { "faq", "Frequently Asked Questions" } };

This notation can seem redundant, but is necessary since G-Cows can handle multidimensional arrays whose elements have different data types. The extra braces allow to distinguish between adding two strings or adding an array of two strings.