How to reorganize the index of the exercices corpus ?

[ghost]

Hi,
I would like to reorganize the index of the exercices corpus like this :

• Week 1: Basic types, definitions and functions
• Week 2: Basic data structures
• Week 3: More advanced data structures
• Week 4: Higher order functions
• Week 5: Exceptions, input/output and imperative constructs
• Week 6: Modules and data abstraction
• Week 7: Advanced Functional Programming

I thought that rewrite the file «exercices/index.json» would be sufficient. Here is my «json» file: index.json . But when I built this command :

learn-ocaml build --repo learn-ocaml-corpus

This message appears :

Learnocaml v.1.0.0 running.
Updating app at ./www
Building ./_learn-ocaml-build/exercises
No case matched:
  Missing object field exercises
  At /groups/week1, no case matched:
    Missing object field exercises
    Missing object field groups

Does anyone have an idea so that the building works ?