👜 Callbag factory that concatenates data from multiple callbag sources
MIT License
/**
npm install callbag-concat
const fromIter = require('callbag-from-iter');
const iterate = require('callbag-iterate');
const concat = require('callbag-concat');
const source = concat(fromIter([10,20,30]), fromIter(['a','b']));
iterate(x => console.log(x))(source); // 10
// 20
// 30
// a
// b
*/
const UNIQUE = {};
const concat = (...sources) => (start, sink) => { if (start !== 0) return; const n = sources.length; if (n === 0) { sink(0, () => {}); sink(2); return; } let i = 0; let sourceTalkback; let lastPull = UNIQUE; const talkback = (t, d) => { if (t === 1) lastPull = d; sourceTalkback(t, d); }; (function next() { if (i === n) { sink(2); return; } sources[i](0, (t, d) => { if (t === 0) { sourceTalkback = d; if (i === 0) sink(0, talkback); else if (lastPull !== UNIQUE) sourceTalkback(1, lastPull); } else if (t === 2 && d) { sink(2, d); } else if (t === 2) { i++; next(); } else { sink(t, d); } }); })(); };
export default concat;