Get emoji flag from country code in Ruby

Question

I want to convert a country code like "US" to an Emoji flag, ie transform "US" string to the appropriate Unicode in Ruby.

Here's an equivalent example for Java

Answer 1

Use tr to translate alphabetic characters to their regional indicator symbols:

'US'.tr('A-Z', "\u{1F1E6}-\u{1F1FF}")
#=> "🇺🇸"

Of course, you can also use the Unicode characters directly:

'US'.tr('A-Z', '🇦-🇿')
#=> "🇺🇸"

Answer 2

Here is a port of that to Ruby:

country = 'US'
flagOffset = 0x1F1E6
asciiOffset = 0x41
firstChar = country[0].ord - asciiOffset + flagOffset
secondChar = country[1].ord - asciiOffset + flagOffset
flag = [firstChar, secondChar].pack("U*")