UNPKG

data-interchange

Version:
39 lines (38 loc) 1.73 kB
"use strict"; var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, P, generator) { function adopt(value) { return value instanceof P ? value : new P(function (resolve) { resolve(value); }); } return new (P || (P = Promise))(function (resolve, reject) { function fulfilled(value) { try { step(generator.next(value)); } catch (e) { reject(e); } } function rejected(value) { try { step(generator["throw"](value)); } catch (e) { reject(e); } } function step(result) { result.done ? resolve(result.value) : adopt(result.value).then(fulfilled, rejected); } step((generator = generator.apply(thisArg, _arguments || [])).next()); }); }; Object.defineProperty(exports, "__esModule", { value: true }); exports.boomerang = exports.BOOMERANG_RETURN = void 0; exports.BOOMERANG_RETURN = Symbol(); /** * Iterate over an array and return when a certain point is met * - Asynchronously iterate over an array of items until the * return symbol is returned, which causes the boomerang to * walk backwards over the list again */ function boomerang(arr, cb) { return __awaiter(this, void 0, void 0, function* () { let shouldReturn = false, returnIndex; for (let ind = 0; ind < arr.length; ind += 1) { let ret = yield cb(arr[ind], ind, false); if (ret === exports.BOOMERANG_RETURN) { shouldReturn = true; returnIndex = ind - 1; break; } } if (shouldReturn && returnIndex >= 0) { for (let ind = returnIndex; ind >= 0; ind -= 1) { yield cb(arr[ind], ind, true); } } }); } exports.boomerang = boomerang;