map-merge.s

map-merge.s

Merges packets of two streams using map function

Installation

npm install map-merge.s

Example

var merge   = require('../lib/map-merge.s.js');
var numbers = require('stream-spectrum/readable/number');
var inspect = require('inspect-stream');

var sum   = merge(function (first, second, done) {
  done(null, first + second);
});

var power = merge(function (first, second, done) {
  done(null, Math.pow(first, second));
});

numbers({ from: 1, to: 8, objectMode: true }).pipe(sum);
numbers({ from: 2, to: 9, objectMode: true }).pipe(sum);
sum.pipe(inspect()); // Outputs 3, 5, 7, 9, 11, 13, 15, 17

numbers({ from: 1, to: 4, objectMode: true }).pipe(power);
numbers({ from: 1, to: 3, objectMode: true }).pipe(power);
power.pipe(inspect()); // Outputs 1, 4, 27. Last packet (4^?) was droped

API

var merge = require('map-merge.s');

var stream = merge(mapFoo)

Creates transform stream that will merge packets from two streams using map function

• mapFoo(first, second, callback) Function. Accepts
  • first Mixed Packet from first stream
  • second Mixed Packet from second stream
  • callback Function Accepts error and result of mapping

Note: If one of streams is longer, then packets from it will be droped