From: Johan Holmberg <holmberg@...>
Date: 2004-01-15T00:33:41+09:00
Subject: Concatenating variable number of Arrays ?


Hi!

I have been searching for a method to concatenate several arrays.
A had an Array like this

     arr1 = [ [1,2,3], [4,5,6], [7,[8,9]] ]

and wanted to produce

     arr2 = [1, 2, 3, 4, 5, 6, 7, [8, 9]]

Looking at the methods of the Array class I found some methods that
do similar things, but none that fits exactly:

    +          concatenate TWO Arrays

    concat     concatenate TWO arrays destructively modifying
               the first

    flatten    RECURSIVELY flattens elements into a new Array


The best way I have found until now, of doing what I want is

    arr2 = arr1.inject([]) {|acc,x| acc.concat x}


But I feel that the thing I want to do (concatenating a variable
number arrays) is such a natural thing, that it deserves a cleaner
way of being expressed.

Have I  missed some other method that does this in a readable way ?

/Johan Holmberg