This includes a few separate changes:
- pass visibility information of declarations (depending on wether the
declaration was in a ```catala-metadata block or not)
- add reasonable hash computation functions to discriminate the interfaces. In
particular:
* Uids have a `hash` function that depends on their string, but not on their
actual uid (which is not stable between runs of the compiler) ; the existing
`hash` function and its uses have been renamed to `id`.
* The `Hash` module provides the tools to properly combine hashes, etc. While
we rely on `Hashtbl.hash` for the atoms, we take care not to use it on any
recursive structure (it relies on a bounded traversal).
- insert the hashes in the artefacts, and properly check and report those (for
OCaml)
**Remains to do**:
- Record and check the hashes in the other backends
- Provide a way to get stable inline-test outputs in the presence of module
hashes
- Provide a way to write external modules that don't break at every Catala
update.
They are to become citizens of the same class if we want to allow
output-subscopes (without unnecessary complications like deconstructing and
reconstructing the same structure). And it's reasonable to assume that they
share the same namespace.
With this we should shortly collapse the (internal) ambiguity between
- `subscope.subvar`: access to a variable within a subscope
- `subscope.subfield`: access to a field of the output structure contained in a
subscope variable
With the subscope a variable, these should now become strictly equivalent, so
the plan is that the first could be removed.
This changes the `decl_ctx` to be toplevel only, with flattened references to
uids for most elements. The module hierarchy, which is still useful in a few
places, is kept separately.
Module names are also changed to UIDs early on, and support for module aliases
has been added (needs testing).
This resolves some issues with lookup, and should be much more robust, as well
as more convenient for most lookups.
The `decl_ctx` was also extended for string ident lookups, which avoids having
to keep the desugared resolution structure available throughout the compilation
chain.
rather than scattered in structures
The context is still hierarchical for defs though, so one needs to retrieve the
path to lookup in the correct context for info. Exceptions are enums and struct
defs, which are re-exposed at toplevel.
(first working dynload test with compilation done by manual calls to ocaml)
A few pieces of the puzzle:
* Loading of interfaces only from Catala files
* Registration of toplevel values in modules compiled to OCaml, to allow access
using dynlink
* Shady conversion from OCaml runtime values to/from Catala expressions, to
allow interop (ffi) of compiled modules and the interpreter
The module is renamed to `Mark`, and functions renamed to avoid redundancy:
`Marked.mark` is now `Mark.add`
`Marked.unmark` is now `Mark.remove`
`Marked.map_under_mark` is now simply `Mark.map`
etc.
`Marked.same_mark_as` is replaced by `Mark.copy`, but with the arguments
swapped (which seemed more convenient throughout)
Since a type `Mark.t` would indicate a mark, and to avoid confusion, the type
`Marked.t` is renamed to `Mark.ed` as a shorthand for `Mark.marked` ; this part
can easily be removed if that's too much quirkiness.
This adds a few positions to the parser, and tweaks some others, vastly
improving the reporting of some errors (inconsistent functions definitions, but
also exceptions cycles, etc.)
Using them will lead to "not supported yet" errors soon after, but it's a start
to get to handling separate modules.
The idea is that `foo` can now also be `Bar.foo`, `Bar.Baz.foo`, `foo.Struc.fld`
can be `foo.Bar.Baz.Struc.fld`, etc.
The next steps are to enable the lookups to handle this paths, and to provide
ways to load the external modules to feed these lookups.
This is just a bunch of `sed` calls:
```shell
sed -i 's/ScopeSet/ScopeName.Set/g' compiler/**/*.ml*
sed -i 's/ScopeMap/ScopeName.Map/g' compiler/**/*.ml*
sed -i 's/StructMap/StructName.Map/g' compiler/**/*.ml*
sed -i 's/StructSet/StructName.Set/g' compiler/**/*.ml*
sed -i 's/EnumMap/EnumName.Map/g' compiler/**/*.ml*
sed -i 's/EnumSet/EnumName.Set/g' compiler/**/*.ml*
sed -i 's/StructFieldName/StructField/g' compiler/**/*.ml*
sed -i 's/StructFieldMap/StructField.Map/g' compiler/**/*.ml*
sed -i 's/StructFieldSet/StructField.Set/g' compiler/**/*.ml*
sed -i 's/EnumConstructorMap/EnumConstructor.Map/g' compiler/**/*.ml*
sed -i 's/EnumConstructorSet/EnumConstructor.Set/g' compiler/**/*.ml*
sed -i 's/RuleMap/RuleName.Map/g' compiler/**/*.ml*
sed -i 's/RuleSet/RuleName.Set/g' compiler/**/*.ml*
sed -i 's/LabelMap/LabelName.Map/g' compiler/**/*.ml*
sed -i 's/LabelSet/LabelName.Set/g' compiler/**/*.ml*
sed -i 's/ScopeVarMap/ScopeVar.Map/g' compiler/**/*.ml*
sed -i 's/ScopeVarSet/ScopeVar.Set/g' compiler/**/*.ml*
sed -i 's/SubScopeNameMap/SubScopeName.Map/g' compiler/**/*.ml*
sed -i 's/SubScopeNameSet/SubScopeName.Set/g' compiler/**/*.ml*
```
... and reformat
