--- title: append_to_list summary: X4 interface reference. Types are established only within the stated scope. section: reference kind: api status: reference updated: 2026-10-26 tags: ["API","X4"] sources: ["https://wiki.egosoft.com/X4%20Foundations%20Wiki/Modding%20Support/","https://www.lua.org/manual/5.1/manual.html","https://luajit.org/ext_ffi_api.html"] --- ## Return value | Type | Meaning | | --- | --- | | [`none`](wiki:type-results) (MD action) | Types describe the declared interface, not proof of a successful game effect. | [Types and methods](wiki:types) ## XML attributes [How schema types work](wiki:schema-types) `libraries/common.xsd` | Attribute | Schema type | Required | Default / fixed | | --- | --- | --- | --- | | `chance` | [`expression`](wiki:schema-expression-b8bc0e4f) | no | not declared | | `weight` | [`expression`](wiki:schema-expression-b8bc0e4f) | no | not declared | | `comment` | [`comment`](wiki:schema-comment-c44bb2fd) | no | not declared | | `name` | [`expression`](wiki:schema-expression-b8bc0e4f) | yes | not declared | | `create` | [`boolean`](wiki:schema-boolean-bf84d3d6) | no | not declared | | `unique` | [`boolean`](wiki:schema-boolean-bf84d3d6) | no | not declared | | `exact` | [`expression`](wiki:schema-expression-b8bc0e4f) | no | not declared | | `list` | [`expression`](wiki:schema-expression-b8bc0e4f) | no | not declared | | `min` | [`expression`](wiki:schema-expression-b8bc0e4f) | no | not declared | | `max` | [`expression`](wiki:schema-expression-b8bc0e4f) | no | not declared | | `profile` | [`profilelookup`](wiki:schema-profilelookup-a6f1cc04) | no | not declared | | `scale` | [`inline:append_to_list@scale`](wiki:schema-inline-append-to-list-scale-2ce6f240) | no | not declared | | `seed` | [`fixedrandomseed`](wiki:schema-fixedrandomseed-6fa38dae) | no | not declared | | `autoadvanceseed` | [`autoadvancerandomseed`](wiki:schema-autoadvancerandomseed-1fb31fa3) | no | not declared | An MD action can write to a named variable or change the world. This is not a Lua return value. The output variable depends on the action and its attributes. ## Example and context See [language basics](wiki:x4-code-basics), [types and methods](wiki:types) and [Lua / MD events](wiki:md-lua-bridge). Examples there are independent learning examples. No project source files or private implementation fragments are distributed with this reference.