9. The tag system

Another of iffinity's strengths, its tag system enables the author to have a fine-grained control over the way their logic and/or styles are organized across their story.

Every snippet can have 0 or more tags:

<snippet name="A Snippet" tags="TAG1 TAG2 TAG3">
    ....
</snippet>

The author can define rules in the configuration file, that bind the snippets that satisfy them to certain scripts and/or styles.

Let's take a look at the configuration file of the convoluted example:

{
    "story": {
        "title": "Three Snippets",
        "author": {
            "name": "Sotiris Niarchos"
        },
        "version": "1.0.0"
    },
    "scripts": {
        "story": "scripts/story.js",
        "global": "scripts/global.js",
        "tags": [
            {
                "rule": "THE_WILD",
                "files": "scripts/the-wild.js"
            },
            {
                "rule": "CASTLE",
                "files": "scripts/castle.js"
            },
            {
                "rule": "THE_WILD && CASTLE",
                "files": "scripts/the-wild-and-castle.js"
            }
        ]
    },
    "styles": {
        "story": "styles/story.css",
        "tags": [
            {
                "rule": "THE_WILD",
                "files": "styles/the-wild.css"
            }
        ]
    }
}

Observe the scripts.tags and styles.tags arrays. There are rules that apply the script scripts/the-wild.js to any snippet with the THE_WILD tag, the script scripts/castle.js to any snippet with the CASTLE tag, and the stylesheet styles/the-wild.css to any snippet with the THE_WILD tag. But there is one more rule in the scripts.tags array that applies the script scripts/the-wild-and-castle.js to any snippet that has both the THE_WILD and CASTLE tags.

You can create any logical expression of tags in your rules, following the JavaScript syntax and using:

• parentheses (( and )),
• the AND operator (&&),
• the OR operator (||), and
• the NOT operator (!).

Note that the standard precedence for logical operators holds, i.e. in the absence of parentheses, NOT is applied before AND, which is applied before OR.