Python nbtlib can't append a Compound to a List

Question

I am trying to add a Compound to a List to make a Compound List:

import nbtlib
from nbtlib.tag import *

CpdList = List(Compound())
Cpd = Compound()

Cpd['name'] = String("Name")
Cpd['test'] = Byte(0)

CpdList.append(Cpd)

This returns the following error:

>>> nbtlib.tag.IncompatibleItemType: Compound({'name': String('Name'), 'test': Byte(0)}) should be a End tag

I don't understand what an End tag is, and how to solve this issue.

I tried adding an End tag to the Compound, but without success:

Cpd['End'] = End

Answer 1

• You just need to properly use nbtlib.tag.List with the Compound type and properly make a call:

import nbtlib
from nbtlib.tag import Compound, List, String, Byte

CpdList = List[Compound]()
Cpd = Compound()
Cpd['name'] = String("Name")
Cpd['test'] = Byte(0)

CpdList.append(Cpd)

print(CpdList)

Note:

Note that the nbtlib.tag.List expects the same type of elements, and the Compound type is not directly allowed in a List tag. The error mentions the need for an End tag, which is a terminator for Compound tags.

---

In case you need a dynamic type list, you can use python native list():

import nbtlib
from nbtlib.tag import Compound, String, Byte

CpdList = list[Compound]()
Cpd = Compound()
Cpd['name'] = String("Name")
Cpd['test'] = Byte(0)

CpdList += [Cpd, 0, 'alice', {1: 2}]

print(CpdList)

Prints

[Compound({'name': String('Name'), 'test': Byte(0)}), 0, 'alice', {1: 2}]

---

Which is same as:

import nbtlib
from nbtlib.tag import Compound, String, Byte

CpdList = list(Compound())
Cpd = Compound()
Cpd['name'] = String("Name")
Cpd['test'] = Byte(0)

CpdList += [Cpd, 0, 'alice', {1: 2}]

print(CpdList)