catala/french_law
Louis Gesbert 41d6d3cbe9 Make scopes directly callable
Quite a few changes are included here, some of which have some extra
implications visible in the language:

- adds the `Scope of { -- input_v: value; ... }` construct in the language

- handle it down the pipeline:
  * `ScopeCall` in the surface AST
  * `EScopeCall` in desugared and scopelang
  * expressions are now traversed to detect dependencies between scopes
  * transformed into a normal function call in dcalc

- defining a scope now implicitely defines a structure with the same name, with
  the output variables of the scope defined as fields. This allows us to type
  the return value from a scope call and access its fields easily.
  * the implications are mostly in surface/name_resolution.ml code-wise
  * the `Scope_out` struct that was defined in scope_to_dcalc is no longer
    needed/used and the fields are no longer renamed (changes some outputs; the
    explicit suffix for variables with multiple states is ignored as well)
  * one benefit is that disambiguation works just like for structures when there
    are conflicts on field names
  * however, it's now a conflict if a scope and a structure have the same
    name (side-note: issues with conflicting enum / struct names or scope
    variables / subscope names were silent and are now properly reported)

- you can consequently use scope names as types for variables as well. Writing
  literals is not allowed though, they can only be obtained by calling the
  scope.

Remaining TODOs:

- context variables are not handled properly at the moment

- error handling on invalid calls

- tests show a small error message regression; lots of examples will need
  tweaking to avoid scope/struct name or struct fields / output variable
  conflicts

- add a `->` syntax to make struct field access distinct from scope output var
  access, enforced with typing. This is expected to reduce confusion of users
  and add a little typing precision.

- document the new syntax & implications (tutorial, cheat-sheet)

- a consequence of the changes is that subscope variables also can now be typed.
  A possible future evolution / simplification would be to rewrite subscopes as
  explicit scope calls early in the pipeline. That could also allow to manipulate
  them as expressions (bind them in let-ins, return them...)
2022-10-21 17:17:26 +02:00
..
catala_legifrance Update assets and rename executable 2022-09-08 15:16:39 +02:00
js Merge branch 'master' into aides_logement 2022-10-17 16:42:46 +02:00
ocaml Make scopes directly callable 2022-10-21 17:17:26 +02:00
python Merge branch 'master' into aides_logement 2022-10-17 16:42:46 +02:00
README.md feat(runtime): clean parse_raw_events + add documentation 2022-06-16 11:39:37 +02:00

French Law Libraries

This folder presents a working example of how Catala could be distributed and deployed inside existing applications. Each sub-folder is specialized for a particular programming language, and features a ready-to-use library of all the French public algorithms coded up using Catala so far.

General principles

Let us say you want to deploy a Catala program inside an application written in programming language X. The Catala compiler will translate the source Catala program into X, yielding a new .x source code file. This .x file will export functions corresponding to the scopes of the original Catala program. You can then reuse those exported functions in your application written in X.

OCaml

To see how to deploy Catala programs as an OCaml library, see the dedicated readme.

JS

To see how to deploy Catala programs as a JS library, see the dedicated readme.

Python

To see how to deploy Catala programs as a Python library, see the dedicated readme.