title: Using lapply function within another one avoiding list of lists
body: <p>Supposing an example in R where we use the <code>lapply</code> function within a same function to create an one-level list:</p>
  
  <pre><code>lapply(1:5, function(x)
  {
    r &lt;- sample(4,1)
  
    i&lt;-lapply(1:r, function (y)
    {
      matrix(rep(1*x*y,3))
    })
    i
  })
  </code></pre>
  
  <p>The given result is a two-level list (list of lists) like this one:</p>
  
  <pre><code>[[1]]
  [[1]][[1]]
       [,1]
  [1,]    1
  [2,]    1
  [3,]    1
  
  
  [[2]]
  [[2]][[1]]
       [,1]
  [1,]    2
  [2,]    2
  [3,]    2
  
  [[2]][[2]]
       [,1]
  [1,]    4
  [2,]    4
  [3,]    4
  
  [[2]][[3]]
       [,1]
  [1,]    6
  [2,]    6
  [3,]    6
  
  [[2]][[4]]
       [,1]
  [1,]    8
  [2,]    8
  [3,]    8
  
  
  [[3]]
  [[3]][[1]]
       [,1]
  [1,]    3
  [2,]    3
  [3,]    3
  
  [[3]][[2]]
       [,1]
  [1,]    6
  [2,]    6
  [3,]    6
  
  
  # ...
  </code></pre>
  
  <p>Preserving both <code>lapply</code> functions (or similar ones) and matrices <strong>with equal dimensions</strong>, how we could get an one-level list thus?</p>
  
  <pre><code>[[1]]
       [,1]
  [1,]    1
  [2,]    1
  [3,]    1
  
  [[2]]
       [,1]
  [1,]    2
  [2,]    2
  [3,]    2
  
  [[3]]
       [,1]
  [1,]    4
  [2,]    4
  [3,]    4
  
  # ...
  </code></pre>