diffusion/src/internal/util/function.js

Diffusion JavaScript client

"use strict";
/**
 * @module Util.Function
 *
 * @brief Utility functions for function calls
 */
Object.defineProperty(exports, "__esModule", { value: true });
exports.identity = exports.callWithArguments = exports.curryR = void 0;
/**
 * Basic curry-right; provides partial application with arguments on the right
 *
 * @param fn   the function to call
 * @param args the arguments passed to the function as the trailing arguments
 * @return     the curried function
 */
function curryR(fn) {
    var args = [];
    for (var _i = 1; _i < arguments.length; _i++) {
        args[_i - 1] = arguments[_i];
    }
    return function () {
        var leftArgs = [];
        for (var _i = 0; _i < arguments.length; _i++) {
            leftArgs[_i] = arguments[_i];
        }
        return callWithArguments(fn, leftArgs.concat(args));
    };
}
exports.curryR = curryR;
/**
 * Call a function with arguments passed in as an array
 *
 * Optimisation of `Function.apply` for small number of arguments
 *
 * `Function.apply` is more than 20 times slower than direct function calls
 * see https://jsperf.com/function-versus-function-call-versus-function-apply
 *
 * @param fn   the function to call
 * @param args the arguments in n array
 * @return     the return value of the function call
 */
function callWithArguments(fn, args) {
    // optimise for manageable numbers of arguments
    switch (args.length) {
        case 0:
            return fn();
        case 1:
            return fn(args[0]);
        case 2:
            return fn(args[0], args[1]);
        case 3:
            return fn(args[0], args[1], args[2]);
        case 4:
            return fn(args[0], args[1], args[2], args[3]);
        case 5:
            return fn(args[0], args[1], args[2], args[3], args[4]);
        case 6:
            return fn(args[0], args[1], args[2], args[3], args[4], args[5]);
        case 7:
            return fn(args[0], args[1], args[2], args[3], args[4], args[5], args[6]);
        case 8:
            return fn(args[0], args[1], args[2], args[3], args[4], args[5], args[6], args[7]);
    }
    return fn.apply(fn, args);
}
exports.callWithArguments = callWithArguments;
/**
 * The identity function
 *
 * @param  val a value
 * @return the input value `val`
 */
function identity(val) {
    return val;
}
exports.identity = identity;