The RGB.js sample run fails

[yhe39]

The RGB.js sample doesn't match the new promise-based gpio API.
We change the code:

var red = gpio.open({pin: pins.IO2, direction: 'out'});
to
var red = null;
gipo.open({pin: pins.IO2, direction: 'out'}).then(function(pin){
red = pin;
});

And the same change of the red, green and blue
Then move the setInterval() to the blue gpio.open statements. Then the test pass.

[kenchris]

As this is using promises, maybe the code should be restructured instead to not require var red = null outside

[kenchris]

You can always do stuff like (not sure now we are not using real promises)

Promise p1 = gpio.open ...
Promise p2 = gpio.open ...

Promise.all([p1, p2]).then(function(values) { }) 

[kenchris]

Btw, ES2017 would make this quite similar as before promises

async function run() {
  let led = await gpio.open({pin: pins.LED0, direction: 'out'});

  let red = await gpio.open({pin: pins.IO2, direction: 'out'});
  let green = await gpio.open({pin: pins.IO7, direction: 'out'});
  let blue = await gpio.open({pin: pins.IO8, direction: 'out'});
}

Not sure if we could use babel as a tool for converting this into ES5.1

[kenchris]

It might make sense, so make an example to see if we babel can be used for transpiling newer ES features onto JerryScript.

Example

require("babel-polyfill");

async function run() {
  let red = await gpio.open();
  let blue = await gpio.open();
  gen();
}

run();

becomes

"use strict";

var run = function () {
  var _ref = _asyncToGenerator(regeneratorRuntime.mark(function _callee() {
    var red, blue;
    return regeneratorRuntime.wrap(function _callee$(_context) {
      while (1) {
        switch (_context.prev = _context.next) {
          case 0:
            _context.next = 2;
            return gpio.open();
          case 2:
            red = _context.sent;
            _context.next = 5;
            return gpio.open();
          case 5:
            blue = _context.sent;

            gen();

          case 7:
          case "end":
            return _context.stop();
        }
      }
    }, _callee, this);
  }));

  return function run() {
    return _ref.apply(this, arguments);
  };
}();

function _asyncToGenerator(fn) { return function () { var gen = fn.apply(this, arguments); return new Promise(function (resolve, reject) { function step(key, arg) { try { var info = gen[key](arg); var value = info.value; } catch (error) { reject(error); return; } if (info.done) { resolve(value); } else { return Promise.resolve(value).then(function (value) { return step("next", value); }, function (err) { return step("throw", err); }); } } return step("next"); }); }; }

require("babel-polyfill");

run();

Using .babelrc:

{
  "presets": ["es2015"],
  "plugins": ["syntax-async-generators", "syntax-async-functions", "transform-async-to-generator"]
}

and ./node_modules/.bin/babel test.js

[grgustaf]

Ken's suggestions are still interesting to try out, but the original RGB.js now works again because I've added back a synchronous version of gpio.open.

[yhe39]

Verified. this issue doesn't exist. close this issue