From: "Guy N. Hurst" <gnhurst@...>
Date: 2002-03-19T13:53:50+09:00
Subject: Re: Wanted: slick rubyesqe algorithm

David Corbin wrote:
> 
> Say I've got a list of Objects
> 
>     [ "AB","CD",alpha,"DE",beta,gamma,"FG","HI"]
> 
> I'd like to "compress that", by concatenating adject Strings (but not
> objects of any other type).  The above example would yield
> 
>     [ "ABCD", alpha, "DE", beta, gamma, "FGHI"]
> 
> Can anyone suggest a particular slick ruby-like solution to this?
> 

Here's my contribution:

a.each_index{|i| if String===a[i] then a[i,2]=a[i]+a[i+1] while String===a[i+1] end}


preview:
=======
irb(main):001:0> a=["AB","CD",:alpha,"DE",:beta,:gamma,"FG","HI"]
["AB", "CD", :alpha, "DE", :beta, :gamma, "FG", "HI"]
irb(main):002:0> a.each_index{|i| if String===a[i] then a[i,2]=a[i]+a[i+1] while String===a[i+1] end}
["ABCD", :alpha, "DE", :beta, :gamma, "FGHI"]
irb(main):003:0> a=[:q,"a",:w,:e,"s","d",:r,"f",:t,"g","h","j",:y]
[:q, "a", :w, :e, "s", "d", :r, "f", :t, "g", "h", "j", :y]
irb(main):004:0> a.each_index{|i| if String===a[i] then a[i,2]=a[i]+a[i+1] while String===a[i+1] end}
[:q, "a", :w, :e, "sd", :r, "f", :t, "ghj", :y]
irb(main):005:0>


Guy N. Hurst