/**

• tallbag-map

• ---

• Tallbag operator that applies a transformation on data passing through it.
• Works on either pullable or listenable sources.
• npm install tallbag-map
• Example:

• const fromIter = require('callbag-from-iter');

• const iterate = require('callbag-iterate');

• const map = require('tallbag-map');

• const source = map(x => x * 0.1)(fromIter([10,20,30,40]));

• iterate(x => console.log(x))(source); // 1

•                                       // 2

•                                       // 3

•                                       // 4

*/

const makeShadow = require('shadow-callbag').default;

const map = f => source => (start, sink) => { if (start !== 0) return; let shadow; source(0, (t, d, s) => { if (t === 0) { shadow = makeShadow('map', s); sink(0, d, shadow); } if (t === 1) { const y = f(d); shadow && shadow(1, y); sink(t, y); } if (t === 2) sink(t, d); }); };

module.exports = map;