Identifier (Data Type)

An identifier (also called a resource location) is a String that names something in the game — an item, block, entity type, status effect, power, tag, or a file in a data/resource pack. It’s the single most common value type in Apoli: every type field is an identifier, and so are power, attribute, effect, sound, and many more.

Format#

An identifier is written as namespace:path.

• The namespace groups ids by who owns them — minecraft for vanilla, apoli for this engine, my_pack for your own content.
• The path names the specific thing within that namespace.

If you write only a path with no colon, the namespace defaults to minecraft. So stone and minecraft:stone are the same.

"apoli:attribute"
"minecraft:diamond_sword"
"my_pack:mana"

Legal characters#

Both the namespace and the path may contain only:

• lowercase letters a–z
• digits 0–9
• underscore _, hyphen -, and dot .

The path may additionally contain / to indicate folders (e.g. apoli:textures/rope/rope.png). The namespace may not. There is exactly one colon, separating namespace and path.

Uppercase letters, spaces, and other symbols are not allowed and will cause the file to fail loading.

Where paths point#

For ids that refer to a pack file, the path maps to a folder under that namespace. For example, a power id my_pack:swim is the file data/my_pack/powers/swim.json.

Tags, wildcards, and which is allowed where#

Three rules cover every identifier field in Apoli. You never have to guess which one a particular field follows — the field’s job tells you.

1. A field that matches something also takes a #tag#

If the field asks “is this thing one of X?”, it accepts either a single id or a #-prefixed tag:

{ "type": "apoli:block", "block": "minecraft:oak_log" }
{ "type": "apoli:block", "block": "#minecraft:logs" }

That holds for apoli:block, apoli:entity_type, apoli:type, apoli:prevent_game_event’s event and events, entity_types on a global power set, and every Ingredient entry.

2. A field that is a tag takes the tag id, with # optional#

Some fields only ever hold a tag — the field name says so (tag, event_tag), or the value is documented as a tag (fluid on apoli:submerged_in, apoli:fluid_height and apoli:walk_on_fluid). Write it with or without the #; both mean the same tag:

{ "type": "apoli:in_tag", "tag": "minecraft:logs" }
{ "type": "apoli:in_tag", "tag": "#minecraft:logs" }

3. * means “the file I am written in”#

Anywhere inside a powers, origins, origin_layers, global_powers or skill_trees file, * stands in for that file’s own id:

You write	It becomes (in data/my_pack/powers/sub/stasis.json)
*:*	my_pack:sub/stasis — this file’s full id
*:domain_mode	my_pack:domain_mode — this file’s namespace, your path
*:sub/stasis	my_pack:sub/stasis — folders in the path are fine
#*:heavy	#my_pack:heavy — works for tags too

Use it so a pack can be renamed or re-namespaced without editing every cross-reference:

{
   "type": "apoli:action_on_key_press",
   "entity_action": {
      "type": "apoli:change_resource",
      "resource": "*:sub/stasis",
      "change": -1
   }
}

Inside an apoli:multiple sub-power, *:* is the parent power’s id, not the generated sub-power id — that is what makes "*:*_stasis" the idiom for referring to a sibling sub-power.

4. Everything else needs an exact id#

Fields that name a thing to create or use — block on apoli:set_block, entity_type on apoli:spawn_entity, sound, texture, function, power, resource — take one exact id. A tag has no meaning there, so passing one is an error, and Apoli says so by name rather than complaining about an illegal character:

'#minecraft:logs' is a tag, and this field takes a single id.
Drop the '#', or use the matching in_tag condition.

An unresolved * reports itself the same way, which is what you’ll see if you used a wildcard somewhere Apoli doesn’t expand it.