def replace_child(cls, template: interfaces.objects.Template,
old_child: interfaces.objects.Template,
new_child: interfaces.objects.Template) -> None:
"""Substitutes the old_child for the new_child."""
if 'subtype' in template.vol:
if template.vol['subtype'] == old_child:
template.update_vol(subtype=new_child)
def replace_child(cls, template: interfaces.objects.Template, old_child: interfaces.objects.Template,
new_child: interfaces.objects.Template) -> None:
"""Replace a child elements within the arguments handed to the
template."""
for member in template.vol.members.get('members', {}):
relative_offset, member_template = template.vol.members[member]
if member_template == old_child:
# Members will give access to the mutable members list,
# but in case that ever changes, do the update correctly
tmp_list = template.vol.members
tmp_list[member] = (relative_offset, new_child)
# If there's trouble with mutability, consider making update_vol return a clone with the changes
# (there will be a few other places that will be necessary) and/or making these part of the
# permanent dictionaries rather than the non-clonable ones
template.update_vol(members = tmp_list)