Promises/A+ implementation based on observer pattern. Promises/A+ speciation is a kind of typical solution for asynchronous flow control. All promise instance is a kind of observer's subject and all callback functions are observers of the above subject.

Installation

# using yarn
yarn add promise-then

# using npm
npm i promise-then

Usage

import Promiser from 'promise-then'

const promiser = new Promiser((resolve, reject) => {
  // ... omit unrelated code
  resolve(result) // or reject(reason)
})

promiser.then(
  result => {
    /* get `result` from promiser internal */
  },
  reason => {
    /* handle any error in the promiser */
  }
)

Debug mode

Debug mode only works with Visual Studio Code breakpoint.

# using yarn
yarn run debug

# using npm
npm run debug

Further

• Promises/A+ specification

License

MIT © Bowen Liu