text: module.exports = function array_shift (inputArr) { // eslint-disable-line camelcase
    //  discuss at: https://locutus.io/php/array_shift/
    // original by: Kevin van Zonneveld (https://kvz.io)
    // improved by: Martijn Wieringa
    //      note 1: Currently does not handle objects
    //   example 1: array_shift(['Kevin', 'van', 'Zonneveld'])
    //   returns 1: 'Kevin'
  
    var _checkToUpIndices = function (arr, ct, key) {
      // Deal with situation, e.g., if encounter index 4 and try
      // to set it to 0, but 0 exists later in loop (need to
      // increment all subsequent (skipping current key, since
      // we need its value below) until find unused)
      if (arr[ct] !== undefined) {
        const tmp = ct
        ct += 1
        if (ct === key) {
          ct += 1
        }
        ct = _checkToUpIndices(arr, ct, key)
        arr[ct] = arr[tmp]
        delete arr[tmp]
      }
  
      return ct
    }
  
    if (inputArr.length === 0) {
      return null
    }
    if (inputArr.length > 0) {
      return inputArr.shift()
    }
  }
  