>> let cal = fn(num) { num * 2 }
>> let nunn = [10, cal(20), 0, "hello", fn(l) { l + 1000}]
>> nunn[0]
10

>> nunn[len(nunn)]
ERROR: argument to `len` not supported, got ARRAY

>> nunn[10]
nil

>> nunn[3]
hello

>> nunn[4]
fn(l){(l + 1000)}

>> nunn[4]
fn(l){(l + 1000)}

>> nunn[4]
fn(l){(l + 1000)}

>> nunn[4]
fn(l){(l + 1000)}

>> nunn[4](10)
1010

>> nunn[4](200)
1200

>> nunn[2]()
ERROR: Not a function: INTEGER

>> nunn[2]
0

>> nunn
10, 40, 0, hello, fn(, l){(l + 1000)}

>> nunn[2]
0

>> nunn[1]
40