text: const _ = require( 'wTools' );
  
  /* operations for regular arrays are performed on `unroll-arrays` too  */
  // creating unroll array
  var unroll = _.unrollMake( [ 2, 3, 4 ] );
  var result = _.arrayAppend( unroll, 5 ); // returns [ 2, 3, 4, 5 ]
  
  console.log( _.unrollIs( result ) ); // true
  
  unroll.push( 'str' );
  
  console.log( _.unrollIs( unroll ) ); // true
  
  /* operations for `unroll-arrays` are performed on regular arrays too */
  var arr = [ 0, 1, 2, 3 ];
  var result = _.unrollPrepend( arr, 4 ); // returns [ 4, 0, 1, 2, 3 ]
  
  console.log( _.unrollIs( result ) ); // false
  
  /* unrolling of 'unroll-arrays' */
  
  var unroll1 = _.unrollMake( [ 7, [ 2 ] ] );
  var unroll2 = _.unrollMake( [ 0, 1, 'str' ] );
  var result = _.unrollAppend( unroll1, unroll2 ); // returns [ 7, [ 2 ], 0, 1, 'str' ]
  
  console.log( _.unrollIs( result ) ); //  true
  
  //
  
  var unroll1 = _.unrollMake( [ '5' ] );
  var unroll2 = _.unrollMake( [ 'str', 3, [ 4 ] ] );
  
  // creating an unroll-array from a given array
  var result = _.unrollFrom( [ 1, 2, unroll1, unroll2 ] ); // returns [ 1, 2, '5', 'str', 3, [ 4 ] ]
  
  console.log( _.unrollIs( result ) ); //  true
  
  //
  
  var unroll1 = _.unrollMake( [ '5' ] );
  var unroll2 = _.unrollMake( [ 'str', [ 3 ] ] );
  
  // unrolling elements(that are unroll-array) of the given array
  var result = _.unrollNormalize( [ 0, 7, unroll1, [ unroll2, unroll1 ] ] ); // returns [ 0, 7, '5', [ 'str', [ 3 ],  '5' ] ]
  
  console.log( _.unrollIs( result ) ); // false
  
  /* unrolling of multidimensional 'unroll-arrays' */
  var unroll1 = _.unrollMake( [ 1, 2 ] );
  var unroll2 = _.unrollMake( [ 3, 4 ] );
  var unroll3 = _.unrollMake( [ 5, 6 ] );
  
  unroll1[ 2 ] = unroll2;
  unroll2[ 2 ] = unroll3;
  
  console.log( unroll1 ); // [ 1, 2, [ 3, 4 [ 5, 6 ] ] ]
  console.log( unroll2 ); // [ 3, 4, [ 5, 6 ] ]
  console.log( unroll3 ); // [ 5, 6  ]
  
  var result = _.unrollNormalize( [ unroll1, unroll2, unroll3 ] );
  console.log( result );
  /*
  [
    1, 2, [ 3, 4, [ 5, 6 ] ],
    3, 4, [ 5, 6 ],
    5, 6
  ]
  */
  