Ruby Hash到值数组

Question

I have this:

hash  = { "a"=>["a", "b", "c"], "b"=>["b", "c"] } 

and I want to get to this: [["a","b","c"],["b","c"]]

This seems like it should work but it doesn't:

hash.each{|key,value| value}
=> {"a"=>["a", "b", "c"], "b"=>["b", "c"]} 

Any suggestions?

Answer 1

Also, a bit simpler....

>> hash = { "a"=>["a", "b", "c"], "b"=>["b", "c"] }
=> {"a"=>["a", "b", "c"], "b"=>["b", "c"]}
>> hash.values
=> [["a", "b", "c"], ["b", "c"]]

Ruby doc here

Answer 2

我会用：

hash.map { |key, value| value }

Answer 3

hash.collect { |k, v| v }
#returns [["a", "b", "c"], ["b", "c"]] 

Enumerable#collect takes a block, and returns an array of the results of running the block once on every element of the enumerable. So this code just ignores the keys and returns an array of all the values.

The Enumerable module is pretty awesome. Knowing it well can save you lots of time and lots of code.

Answer 4

hash  = { :a => ["a", "b", "c"], :b => ["b", "c"] }
hash.values #=> [["a","b","c"],["b","c"]]

Answer 5

It is as simple as

hash.values
#=> [["a", "b", "c"], ["b", "c"]]

this will return a new array populated with the values from hash

if you want to store that new array do

array_of_values = hash.values
#=> [["a", "b", "c"], ["b", "c"]]

array_of_values
 #=> [["a", "b", "c"], ["b", "c"]]

Answer 6

There is also this one:

hash = { foo: "bar", baz: "qux" }
hash.map(&:last) #=> ["bar", "qux"]

Why it works:

The & calls to_proc on the object, and passes it as a block to the method.

something {|i| i.foo }
something(&:foo)