Ruby数组哈希

Question

So I have a hash like this:

hash  = { "a"=>[1, 2, 3], "b"=>[18, 21, 9] }

I would like to get the whole array, not just the values.
It seems like this should work:

hash.each{|key,value| value}

[1, 2, 3]
[18, 21, 9]

But what I get is the individual elements of the array-1, 2, 3. I know I can do hash.values, but that gives an array of arrays with no keys. I need the key/value(array) pair. Thoughts?

Answer 1

What you are describing does work as intended:

=> {"a"=>[1, 2, 3], "b"=>[18, 21, 9]}
[4] pry(main)> hash.each { |k,v| puts v.length }
3
3

Can you post a snippet of code illustrating your specific problem?

Answer 2

Your construction does give you the whole array:

irb(main):001:0> hash = { "a" => [1, 2, 3], "b" => [18, 21, 9] }
=> {"a"=>[1, 2, 3], "b"=>[18, 21, 9]}
irb(main):002:0> hash.each{ |key,value| puts value.class.name }
Array
Array

Perhaps you are just trying to puts an array? If so, by default that puts each element on a separate line.

irb(main):003:0> puts [1,2,3]
1
2
3

Answer 3

Not sure if I fully understood but are you asking for something like this (using .to_a ):

hash = { "a"=>[1, 2, 3], "b"=>[18, 21, 9] }
 => {"a"=>[1, 2, 3], "b"=>[18, 21, 9]}
arr = hash.to_a
 => [["a", [1, 2, 3]], ["b", [18, 21, 9]]]

Answer 4

Try this:

hash.map { |k,v| { k => v} }

It returns:

{"a"=>[1, 2, 3]}
{"b"=>[18, 21, 9]}

Answer 5

is this what you want?

hash.map{|key,value| [key]+value }
=> [["a", 1, 2, 3], ["b", 18, 21, 9]]

Answer 6

If you have this

hash = { "a"=>[1, 2, 3], "b"=>[18, 21, 9] }

and you want the whole array to be returned just use the key accessor. For example

hash[:a] = [1, 2, 3]
hash[:b] = [18, 21, 9]