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Defining Models as JSON

Concerto models can be defined using a JSON object, rather than using the CTO syntax. This primarily intended for programmatic definition or editing of models, for example, via a model editor user interface.

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const { ModelManager, ModelFile } = require('@accordproject/concerto-core');

try {
// create the model manager, used to manage a consistent set of
// related models
const mm = new ModelManager();

// defines the namespace for the Concerto metamodel
// the metamodel is here:
const MM = 'concerto.metamodel@1.0.0'

// create a model as a JSON object
// defines an Address concept with three string properties:
// street, city and zip, with zip being an optional property
const modelAst = {
$class: `${MM}.Model`,
namespace: "test@1.0.0",
declarations: [
{ $class: `${MM}.ConceptDeclaration`,
name: "Address",
properties: [
{ $class: `${MM}.StringProperty`, name: "street"},
{ $class: `${MM}.StringProperty`, name: "city"},
{ $class: `${MM}.StringProperty`, name: "zip", isOptional: true}
] }

// validates the JSON model
const modelFile = new ModelFile(mm, modelAst);

// adds the model to the model manager
// and checks consistency

// we can now retrieve a type from the model manager
const addressType = mm.getType('test@1.0.0.Address');
catch (err) {