Source code for openpyxl.descriptors.container

# Copyright (c) 2010-2024 openpyxl

"""
Utility list for top level containers that contain one type of element

Provides the necessary API to read and write XML
"""

from openpyxl.xml.functions import Element



[docs]
class ElementList(list):


    @property
    def tagname(self):
        raise NotImplementedError


    @property
    def expected_type(self):
        raise NotImplementedError



[docs]
    @classmethod
    def from_tree(cls, tree):
        l = [cls.expected_type.from_tree(el) for el in tree]
        return cls(l)




[docs]
    def to_tree(self):
        container = Element(self.tagname)
        for el in self:
            container.append(el.to_tree())
        return container




[docs]
    def append(self, value):
        if not isinstance(value, self.expected_type):
            raise TypeError(f"Value must of type {self.expected_type} {type(value)} provided")
        super().append(value)