@catala-lang/french-law

This folder contains a ready-to-use Javascript library featuring French public algorithms coded up in Catala and the corresponding ReScript wrapper.

Generating the source files

The JS code is extracted from OCaml using js_of_ocaml. See the dedicated README of the OCaml library for more precisions about the OCaml code.

The wrapping between OCaml and JS is done by the generated ../ocaml/law_source/<filename>_api_web.ml modules.

You can generate the french_law.js source JS module by invoking this command from the root of the repository:

make build_french_law_library_js

API description

The ./src/french_law.js library exposes:

• an event manager
• a list of API functions
• a list of fully exposed sub-libraries

ReScript

The ReScript API is essentialy the same that the JS one within the CatalaFrenchLaw top module.

Example of project using the ReScript wrapper:

• catala-website

The event manager

A JavaScript object eventsManager is exposed with three callable methods:

var frenchLaw = require("french_law.js");

// Clears the raw log event array.
frenchLaw.eventsManager.resetLog(0);

// Returns the current content of the raw log event array.
let rawEvents = frenchLaw.eventsManager.retrieveRawEvents(0)

// Returns the event array parsed from the current content of the raw log event array.
let events = frenchLaw.eventsManager.retrieveEvents(0)

Important: you need to give an arbitrary value as argument.

Date and time

Date values are encoded to JS string according the ISO8601 format: 'YYYY-MM-DD'.

API functions

The french_law.js library exposes for each Catala program available in ../ocaml/law_source/ a function to call in order to run the corresponding encoded algorithm.

Available algorithms

Allocations familiales

The function is computeAllocationsFamiliales. This computation returns the amount of allocations familiales for one household described by the input. More precisely, the result returned is the sum of:

• la base des allocations familiales
• l'allocation forfaitaire relai pour dépassement de l'âge limite
• la majoration pour âge
• le complément dégressif en cas de dépassement du plafond de revenus

An example of use:

var frenchLaw = require("french_law.js");

let amount = frenchLaw.computeAllocationsFamiliales({
  iDateCouranteIn: "2020-04-20",
  iEnfantsIn: [
    {
      dIdentifiant: 0,
      dRemunerationMensuelle: 0,
      dDateDeNaissance: "2003-02-02",
      dPriseEnCharge: { kind: "EffectiveEtPermanente", payload: null },
      dADejaOuvertDroitAuxAllocationsFamiliales: true,
      dBeneficieTitrePersonnelAidePersonnelleLogement: false,
    },
    {
      dIdentifiant: 1,
      dRemunerationMensuelle: 300,
      dDateDeNaissance: "2013-09-30",
      dPriseEnCharge: {
        kind: "GardeAlterneePartageAllocations",
        payload: null,
      },
      dADejaOuvertDroitAuxAllocationsFamiliales: true,
      dBeneficieTitrePersonnelAidePersonnelleLogement: false,
    },
  ],
  iRessourcesMenageIn: 30000,
  iResidenceIn: { kind: "Metropole", payload: null },
  iPersonneChargeEffectivePermanenteEstParentIn: true,
  iPersonneChargeEffectivePermanenteRemplitTitreIIn: true,
  iAvaitEnfantAChargeAvant1erJanvier2012In: false,
});

Notably, the dPriseEnCharge variable for each child expects a value among:

• "GardeAlterneePartageAllocations"
• "GardeAlterneeAllocataireUnique"
• "EffectiveEtPermanente"
• "ServicesSociauxAllocationVerseeALaFamille"
• "ServicesSociauxAllocationVerseeAuxServicesSociaux"

See ../ocaml/law_source/allocations_familiales_api_web.ml for more information about data types.

Aides logement

TODO: add information about aides_logement_api_web.ml.

Sub libraries

All declared types and scopes of a Catala program are available in JavaScript via the following sub libs:

var frenchLaw = require("french_law.js");

// Allocations familiales
// corresponding to the file: `../ocaml/law_source/allocations_familiales_api_web.ml
var allocationsFamiliales = frenchLaw.AllocationsFamilialesLib

// APL
// corresponding to the file: `../ocaml/law_source/aides_logement_api_web.ml
var aidesLogement = frenchLaw.AidesLogementLib