Derive Macro LanguageChildren

#[derive(LanguageChildren)]

The macro to define a view type for a LanguageChildren and conversion mechanisms.

The type passed to LanguageChildren must satisfy the following conditions:

1. It MUST have exactly one generic parameter.
2. It MUST be a struct.
3. It MUST have at least one field with one of the following types (where T parameter):
   • T
   • [T; N]
   • Vec<T>
4. Vec<T> can appear AT MOST ONCE.