how to use javascript Object.defineProperty

Question

I looked around for how to use the Object.defineProperty method, but couldn\'t find anything decent.

Someone gave me this snippet of code:

Object.def         


        

Answer 1

import { CSSProperties } from 'react'
import { BLACK, BLUE, GREY_DARK, WHITE } from '../colours'

export const COLOR_ACCENT = BLUE
export const COLOR_DEFAULT = BLACK
export const FAMILY = "'Segoe UI', sans-serif"
export const SIZE_LARGE = '26px'
export const SIZE_MEDIUM = '20px'
export const WEIGHT = 400

type Font = {
  color: string,
  size: string,
  accent: Font,
  default: Font,
  light: Font,
  neutral: Font,
  xsmall: Font,
  small: Font,
  medium: Font,
  large: Font,
  xlarge: Font,
  xxlarge: Font
} & (() => CSSProperties)

function font (this: Font): CSSProperties {
  const css = {
    color: this.color,
    fontFamily: FAMILY,
    fontSize: this.size,
    fontWeight: WEIGHT
  }
  delete this.color
  delete this.size
  return css
}

const dp = (type: 'color' | 'size', name: string, value: string) => {
  Object.defineProperty(font, name, { get () {
    this[type] = value
    return this
  }})
}

dp('color', 'accent', COLOR_ACCENT)
dp('color', 'default', COLOR_DEFAULT)
dp('color', 'light', COLOR_LIGHT)
dp('color', 'neutral', COLOR_NEUTRAL)
dp('size', 'xsmall', SIZE_XSMALL)
dp('size', 'small', SIZE_SMALL)
dp('size', 'medium', SIZE_MEDIUM)

export default font as Font