Kata

Write the method Object#iterate that given an object takes a block as argument and an optional count n.

If n is given it returns an array of length n where each element can obtained by the successive application of the block on the object, starting with the object.

If n is not given, it returns an Enumerator that yields the successive application of the block on the object indefinitely.

Example:

'str'.iterate(3) {|s| s * 2 } # => ["str", "strstr", "strstrstrstr"]

"str".iterate( s => s+s , 3 ) // => ["str", "strstr", "strstrstrstr"]