staples/index.js

exports.printVersion = () => {
  console.log('Staples v0.0.1')
}

exports.compile = (template, input) => {
  let index = 0

  while(index < template.length) {
    const nextOpen = template.indexOf('{{', index + 1)
    if(nextOpen == index || nextOpen == -1) {
      index = template.length
    } else {
      index = nextOpen
      const nextClose = template.indexOf('}}', index + 1)
      if(nextClose == index || nextClose == -1) {
        index = template.length
      } else {
        index = nextOpen+2
        const tagContent = template.substring(nextOpen+2, nextClose)
        const tagContentSplit = tagContent.split('.')
        let varLevel = input
        tagContentSplit.forEach( (level) => {
          const isIndex = Number.isInteger(parseInt(level))
          varLevel = isIndex ? varLevel[parseInt(level)] : varLevel[level]
        })
        template = template.replace(tagContent, varLevel)
      }
    }
  }
  console.log(template)
}