From: Peter Hickman <peter@...>
Date: 2008-05-06T22:54:42+09:00
Subject: Re: trying to create an array with AA-ZZ for dutch postal codes

bookie988@gmail.com wrote:
> the array postcodes should be filled with strings starting looking
> like
>
> ["AA",AB",AC"..."BA","BB","BC" to "ZZ"] 26*26 entries.
>
> i've come up with the following to create it,
>
>  postcodes = Array.new
>
>  # create postal codes array
>
>  W = String.new()
>  X = String.new()
>
>  (A..Z).each do |W| {
>
> 	 puts W
> 	 (A..Z).each do |X|	{
> 			 postcodes.push("#{W}#{X}")
>
> 			 }
> 		 }
>
>  puts(postcodes)
>
> this code produces
>
> hpricot-test.rb:20: syntax error, unexpected tCONSTANT, expecting kDO
> or '{' or '('
> hpricot-test.rb:22: odd number list for Hash
> hpricot-test.rb:25: syntax error, unexpected '}', expecting kEND
> hpricot-test.rb:57: syntax error, unexpected $end, expecting kEND
>
> what am i doing wrong, is there an easier (rubier) way?
>
>
>   
Sorry but there are many errors here: First some code that works:

postcodes = Array.new

('A'..'Z').each do |x|
    ('A'..'Z').each do |y|
        postcodes << "#{x}#{y}"
    end
end

puts(postcodes)

Note that the A..Z is now 'A'..'Z'. This is because A is a reference to
a constant called A which you haven't defined but 'A' is a upper case
letter.

When doing a xxx.each you can do it either way:

('A'..'Z').each do |x|
    puts x
end

or

('A'..'Z').each {|x|
    puts x
}

You seem to be mixing both.

Your use of W and X as variables. Firstly upper case letters are
constants so you can not use them as looping variables. Infact you do
not need to predeclare the variables at all.