[1] "integer"      "numeric"      "integer"      "integer"
[1] "numeric"      "numeric"      "double"       "double" 
[1] "character"    "character"    "character"    "character"
[1] "logical"      "logical"      "logical"      "logical"
[1] "data.frame"   "list"         "list"         "list"      
[1] "data.frame"   "list"         "list"         "list"      
[1] "numeric"      "numeric"      "double"       "double" 
[1] "matrix"       "list"         "list"         "list"  
[1] "environment"  "environment"  "environment"  "environment"
[1] "expression"   "expression"   "expression"   "expression"
[1] "<-"           "call"         "language"     "language"
[1] "function"     "function"     "function"     "closure"