Get all keys from a hash


hash = {1 => 2, 2 => 2, 3 => 10}
p hash.keys                                    # => [1, 2, 3]

1.	Return an array containing all the keys in a hash with keys:
2.	Extract data from the hash by using its keys.
3.	Use number as hash key
4.	Retrieving Keys
5.	Join hash keys together
6.	RuntimeError: hash modified during iteration
7.	Time value key
8.	Searching a Hash with Regular Expressions
9.	What if a key does not exist
10.	Hash as a key

Get all keys from a hash : Hash Keys « Hash « Ruby