Convenient way to get many hash elements at once.

[Ron M]

If I have a hash table with a bunch of fields; and I want to
extract a subset of them, kinda like "@a_hashtable{'a','c'}"
in perl, is there a nice way of doing so?
I was hoping something like this would work...

h={'first name'=>'John', 'last name'=>'Doe', 'birthday'=>'1970-01-01', 'height'=>'5 foot'}

h['first name','last name'] # hoping for ['John','Doe'] as a result.

but it gave me

ArgumentError: wrong number of arguments (2 for 1)
from (irb):126:in `[]'
from (irb):126
from ^C:0

I suppose
['first name','last name'].map{|x| h[x]}
does what I want; but it surely isn't as readable as
h['first name','last name']

If there's no cleaner way of doing this; would it be a reasonably
Ruby 2.0 request to allow Hash#[] to take multiple arguments and
return multiple return values for each of the arguments?

[Simon Strandgaard]

On 10/17/05, Ron M <rm_r...@cheapcomplexdevices.com> wrote:
> If I have a hash table with a bunch of fields; and I want to
> extract a subset of them, kinda like "@a_hashtable{'a','c'}"
> in perl, is there a nice way of doing so?
> I was hoping something like this would work...
>
> h={'first name'=>'John', 'last name'=>'Doe', 'birthday'=>'1970-01-01', 'height'=>'5 foot'}
>
> h['first name','last name'] # hoping for ['John','Doe'] as a result.
>

h.values_at('first name', 'last name')
#=> ["John", "Doe"]

--
Simon Strandgaard