Joel VanderWerf
7/12/2006 8:52:00 PM
don mc wrote:
> Is there a succinct way in ruby to do a multiple level hash assignement?
> I am more
> used to perl, which you can do something like
>
>
> $hp->{level1}->{level2} = 3
>
> even if the first and second level had never existed below.
There's an autovivification trick, using the default proc of a hash (see
ri default_proc):
irb(main):002:0> pr = proc {|h,k| h[k]=Hash.new(&pr) }
=> #<Proc:0x02c15618@(irb):2>
irb(main):003:0> h = Hash.new(&pr)
=> {}
irb(main):004:0> h[1][2][3][4] = 5
=> 5
irb(main):005:0> h
=> {1=>{2=>{3=>{4=>5}}}}
--
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