From: Logan Capaldo <logancapaldo@...>
Date: 2005-05-26T05:52:51+09:00
Subject: Re: loop over array with indices

On 5/25/05, Pit Capitain <pit@capitain.de> wrote:
> Logan Capaldo schrieb:
> >
> > You may want to write your own inject for this.
> >
> >   def inject_with_index(*args)
> >     ...
> >   end
> >
> > Then you can call it less weirdly:
> >
> > ["a", "b", "c"].inject_with_index("") { |a, b, i| a << "#{b}@#{i}" }
> > #=> "a@0b@1c@2"
> >
> > ["a", "b", "c"].inject_with_index do |a, i1, b, i2|
> >     [a + b, i1 + i2]
> > end
> > #=> ["abc", 3]
> 
> Hi Logan,
> 
> note you can have almost the same syntax with the normal inject:
> 
>    arr_iter.inject("") { |a, (b, i)| a << "#{b}@#{i}" }
>    # => "a@0b@1c@2"
> 
>    arr_iter.inject { |(a, i1), (b, i2)| [a + b, i1 + i2] }
>    # => ["abc", 3]
> 
> Regards,
> Pit
> 
> 

Aha. That's really cool. I did not know that.