simple-squiggle/node_modules/mathjs/lib/esm/utils/factory.js

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import { contains } from './array.js';
import { pickShallow } from './object.js';
/**
* Create a factory function, which can be used to inject dependencies.
*
* The created functions are memoized, a consecutive call of the factory
* with the exact same inputs will return the same function instance.
* The memoized cache is exposed on `factory.cache` and can be cleared
* if needed.
*
* Example:
*
* const name = 'log'
* const dependencies = ['config', 'typed', 'divideScalar', 'Complex']
*
* export const createLog = factory(name, dependencies, ({ typed, config, divideScalar, Complex }) => {
* // ... create the function log here and return it
* }
*
* @param {string} name Name of the function to be created
* @param {string[]} dependencies The names of all required dependencies
* @param {function} create Callback function called with an object with all dependencies
* @param {Object} [meta] Optional object with meta information that will be attached
* to the created factory function as property `meta`.
* @returns {function}
*/
export function factory(name, dependencies, create, meta) {
function assertAndCreate(scope) {
// we only pass the requested dependencies to the factory function
// to prevent functions to rely on dependencies that are not explicitly
// requested.
var deps = pickShallow(scope, dependencies.map(stripOptionalNotation));
assertDependencies(name, dependencies, scope);
return create(deps);
}
assertAndCreate.isFactory = true;
assertAndCreate.fn = name;
assertAndCreate.dependencies = dependencies.slice().sort();
if (meta) {
assertAndCreate.meta = meta;
}
return assertAndCreate;
}
/**
* Sort all factories such that when loading in order, the dependencies are resolved.
*
* @param {Array} factories
* @returns {Array} Returns a new array with the sorted factories.
*/
export function sortFactories(factories) {
var factoriesByName = {};
factories.forEach(factory => {
factoriesByName[factory.fn] = factory;
});
function containsDependency(factory, dependency) {
// TODO: detect circular references
if (isFactory(factory)) {
if (contains(factory.dependencies, dependency.fn || dependency.name)) {
return true;
}
if (factory.dependencies.some(d => containsDependency(factoriesByName[d], dependency))) {
return true;
}
}
return false;
}
var sorted = [];
function addFactory(factory) {
var index = 0;
while (index < sorted.length && !containsDependency(sorted[index], factory)) {
index++;
}
sorted.splice(index, 0, factory);
} // sort regular factory functions
factories.filter(isFactory).forEach(addFactory); // sort legacy factory functions AFTER the regular factory functions
factories.filter(factory => !isFactory(factory)).forEach(addFactory);
return sorted;
} // TODO: comment or cleanup if unused in the end
export function create(factories) {
var scope = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : {};
sortFactories(factories).forEach(factory => factory(scope));
return scope;
}
/**
* Test whether an object is a factory. This is the case when it has
* properties name, dependencies, and a function create.
* @param {*} obj
* @returns {boolean}
*/
export function isFactory(obj) {
return typeof obj === 'function' && typeof obj.fn === 'string' && Array.isArray(obj.dependencies);
}
/**
* Assert that all dependencies of a list with dependencies are available in the provided scope.
*
* Will throw an exception when there are dependencies missing.
*
* @param {string} name Name for the function to be created. Used to generate a useful error message
* @param {string[]} dependencies
* @param {Object} scope
*/
export function assertDependencies(name, dependencies, scope) {
var allDefined = dependencies.filter(dependency => !isOptionalDependency(dependency)) // filter optionals
.every(dependency => scope[dependency] !== undefined);
if (!allDefined) {
var missingDependencies = dependencies.filter(dependency => scope[dependency] === undefined); // TODO: create a custom error class for this, a MathjsError or something like that
throw new Error("Cannot create function \"".concat(name, "\", ") + "some dependencies are missing: ".concat(missingDependencies.map(d => "\"".concat(d, "\"")).join(', '), "."));
}
}
export function isOptionalDependency(dependency) {
return dependency && dependency[0] === '?';
}
export function stripOptionalNotation(dependency) {
return dependency && dependency[0] === '?' ? dependency.slice(1) : dependency;
}