obj-hex-conversion.js

// This script transforms hex numbers in objects to hex-strings (for more elegant style-code)

// The number-to-hex-string conversion
const hex = num => `#${ num.toString(16) }`

// Entries in objects that should be transformed
const TRANSFORM_ENTRIES = [
  "backgroundColor",
  "color"
];

// Maps through an object and transforms numbers to hex-strings
function transformStyleObj(obj) {
  const res = {}

  Object.entries(obj)
    .map(entry => {
      if (!isNaN(entry[1]) && TRANSFORM_ENTRIES.includes(entry[0]))
        entry[1] = hex(entry[1])

      res[entry[0]] = entry[1]
    })

  return res
}


const style =                  { backgroundColor:  0x222, color:  0xfff }
transformStyleObj(style) // => { backgroundColor: "#222", color: "#fff" }