Question

I am using Ruby 1.8.7 (and upgrading isn’t an option). I would like to create a string of all UTF-8 code points from 0 to 127, written as “\uXXXX”.

My problem is that this is being interpreted as (for example): ‘u0008’. If I try to use ‘\u0008’, the string becomes “\u0008” which IS NOT what I want.

I have tried many different ways, but it seems impossible to create a string that is exactly just “\uXXXX” ie. “\u000B”. it always is either “\u000B” or “u000B”

Escaping the ‘\’ isn’t an option. I need to send a string to a server, such that the server will receive ‘\u000B’ for example. It is so that other server can test its parsing of the \uXXXX syntax. This seems impossible to do in Ruby however.

Happy if someone can prove me wrong 🙂

Answer 1

Use Integer #chr to get the character. Here’s a clean version:

(1..127).each do |i|
  value << "U+#{i} = #{i.chr}, hex = \\x#{"%02x" % i}; "
end

The "%02x" % i is the equal to sprintf("%02x", i). It returns the integer as a 2-digit hexadecimal number.

Escaped output (see comments):

(1..127).each do |i|
  value << "U+#{i} = \\u#{"%04x" % i}, hex = \\x#{"%02x" % i}; "
end