add_stop_byte.coffee.md

Add stop byte

Given an object with start_byte and bytes values, this sets their sum to the stop_byte property.

Library imports

R = require 'ramda'

{both, identity, juxt, mergeAll, objOf, pipe, propIs, props, sum} = R

Helper functions

calculate_stop_byte = pipe(props(['bytes', 'start_byte']), sum, objOf('stop_byte'))

calculate_and_merge = pipe(juxt([identity, calculate_stop_byte]), mergeAll)

has_properties = both(propIs(Number, 'bytes'), propIs(Number, 'start_byte'))

Exports

module.exports = R.when(has_properties, calculate_and_merge)