re = /^\+65(\s?)[689]\d{3}\1\d{4}$/m
str = '+6581234567
+65 8123 4567
+65 81234567
+658123 4567
'
# Print the match result
str.scan(re) do |match|
puts match.to_s
end
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Ruby, please visit: http://ruby-doc.org/core-2.2.0/Regexp.html