New Post: Is Javascript .NET secure for runtime code? (purpose: edit xml file using custom javascript)

I have a CLI application which is able to edit XML files with some parameters.

However I'm needing now a more powerful way to do it.

I want to give users the option to edit XML files using custom code from a .txt for total control over the XML editing.

For example:

@CODE File<file name for XML editing>
<code>
# Custom XML parser/editing code
for elem in tree.iter(tag='location'):
if elem.text == 'J':
    elem.text = 'January'
</code>

Is Javascript.net (javascript) secure to do this? I mean the user only be able to edit the XML file and not doing anything more that compromises the security of the system (like deleting system files)?