Rails displaying a string as an array - html

Question

First off, I apologize in advance for any incorrect terms or general misunderstanding of ruby/rails/html that I may display in this question, as I'm still learning the languages and how they work. I've been given a gui to work on and fix bugs for and after upgrading from rails 3.0 to 3.2 I'm seeing artifacts in many places.
Specifically what I'm asking in this post though is a string display issue. The short version of what I have is a message thread displayed with in a web page that looks close to what you'd see in most text message clients on smartphones now days. The page displays a persons name if the system knows who they are (registered with us) and just a mobile number if they are not.
However the issue is that instead of displaying 5554440002, it's displaying as:
["(", "5", "5", "5", ")", " ", "4", "4", "4", "-", "0", "0", "0", "1"]
Looking around the net, and on stack overflow I found this post To be the closest thing to answering my issue. However the suggestion of dropping the = out of <%= ends in the mobile number no longer displaying.
The line of code that generates this output is:
<%= find_associated_account conversation_message['from'] -%>
Edit 1 (definition):
def find_associated_account(input)
if input[0..0] == $operator.domestic_code.to_s
input = input[1..10]
end
if #account.associated_accounts and #account.associated_accounts.count > 0
if !(input.match(/#/)) && !(input.match(/MISSING_MAILBOX/))
input = input[0..9]
end
begin
acc = #account.associated_accounts.find_by_number(input)
if acc
return get_display_name_for_account(acc)
end
end
return format_mdn(input)
end
def format_mdn(input)
domestic_length = $operator.domestic_mask.count('#')
number_cc_stripped = input.sub(/\A[#{$operator.domestic_code}]/, '')
if /^[0-9]{#{domestic_length}}$/.match(number_cc_stripped)
result = []
count = 0
$operator.domestic_mask.each_char do |c|
if c == '#'
result << number_cc_stripped[count,1]
count += 1
else
result << c
end
end
return result.to_s
end
return input
end
Any advice given will be greatly appreciated and any other information needed will be provided.

Answer 1

Fixed this after messing with the return value of format_mdn. I changed the initialization of result to "" instead of [] which I'm guessing changed the type of the variable? In any case the final code for this definition is:
def format_mdn(input)
domestic_length = $operator.domestic_mask.count('#')
number_cc_stripped = input.sub(/\A[#{$operator.domestic_code}]/, '')
if /^[0-9]{#{domestic_length}}$/.match(number_cc_stripped)
result = []
count = 0
$operator.domestic_mask.each_char do |c|
if c == '#'
result << number_cc_stripped[count,1]
count += 1
else
result << c
end
end
return result.join("")
end
result = number_cc_stripped
return result
end