var async = require('./async.js')
, abort = require('./abort.js') ;
// API module.exports = iterate;
/**
* Iterates over each job object * * @param {array|object} list - array or object (named list) to iterate over * @param {function} iterator - iterator to run * @param {object} state - current job status * @param {function} callback - invoked when all elements processed */
function iterate(list, iterator, state, callback) {
// store current index var key = state['keyedList'] ? state['keyedList'][state.index] : state.index; state.jobs[key] = runJob(iterator, key, list[key], function(error, output) { // don't repeat yourself // skip secondary callbacks if (!(key in state.jobs)) { return; } // clean up jobs delete state.jobs[key]; if (error) { // don't process rest of the results // stop still active jobs // and reset the list abort(state); } else { state.results[key] = output; } // return salvaged results callback(error, state.results); });
}
/**
* Runs iterator over provided job element * * @param {function} iterator - iterator to invoke * @param {string|number} key - key/index of the element in the list of jobs * @param {mixed} item - job description * @param {function} callback - invoked after iterator is done with the job * @returns {function|mixed} - job abort function or something else */
function runJob(iterator, key, item, callback) {
var aborter; // allow shortcut if iterator expects only two arguments if (iterator.length == 2) { aborter = iterator(item, async(callback)); } // otherwise go with full three arguments else { aborter = iterator(item, key, async(callback)); } return aborter;
}