From: Luc Heinrich <luc@...>
Date: 2010-02-26T03:39:29+09:00
Subject: Re: Array index question

On 25 févr. 2010, at 19:20, David Springer wrote:

> textlist = ["Apple", "Orange", "Lemon", "Grape", "Orange", 
> "Melon","Orange", "Banana"]
> 
> i = textlist.index("Orange")
> 
> if !i.nil?
>        puts "textlist[" << i.to_s << "] is \"" << textlist[i] << "\""
>  j = textlist[i+1,textlist.length-i-1].index("Orange")+i+1
>        if !j.nil?
>          puts "textlist[" << j.to_s << "] is \"" << textlist[j] << "\""
>        end
> end

class Array
    def indexes_of(obj)
        indexes = Array.new
        self.each_with_index {|s,i| indexes << i if s === obj }
        return indexes
    end
end

textlist = ["Apple", "Orange", "Lemon", "Grape", "Orange", "Melon","Orange", "Banana"]
p textlist.indexes_of("Orange")

#=> [1,4,6]

-- 
Luc Heinrich - luc@honk-honk.com