From: Robert Klemme <shortcutter@...>
Date: 2011-10-12T17:42:44+09:00
Subject: Re: array of hashes

On Tue, Oct 11, 2011 at 7:07 PM, Mario Ruiz <tcblues@gmail.com> wrote:
> I have an array of hashes like this:
> a=Array.new()
> a.push({:name=>"mario",:value=>"xxx"})
> a.push({:name=>"pedro",:value=>"lsss"})
>
> and I would like to get a value of the array knowing the :name by doing
> something like:
> a.each {|h|
>  if h[:name]=="mario" then value=h[:value]
> }
>
> but just in one line, is that possible?

Here's another suggestion: you can use rescue to avoid the error you
get if nothing is found:

irb(main):001:0> a=[]
=> []
irb(main):002:0> a << {:name=>"mario",:value=>"xxx"}
=> [{:name=>"mario", :value=>"xxx"}]
irb(main):003:0> a << {:name=>"pedro",:value=>"lsss"}
=> [{:name=>"mario", :value=>"xxx"}, {:name=>"pedro", :value=>"lsss"}]
irb(main):004:0> a

irb(main):006:0> a.find {|h| h[:name] == 'mario'}[:value] rescue nil
=> "xxx"
irb(main):007:0> a.find {|h| h[:name] == 'missing'}[:value] rescue nil
=> nil

It's probably cleaner though to do

irb(main):008:0> r = a.find {|h| h[:name] == 'mario'} and r[:value]
=> "xxx"
irb(main):009:0> r = a.find {|h| h[:name] == 'missing'} and r[:value]
=> nil

Kind regards

robert

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