[ruby/psych] tr is typically 4 to 5 times faster than gsub

https://github.com/ruby/psych/commit/8533be8fe7

ext/psych/lib/psych/scalar_scanner.rb

@@ -95,7 +95,7 @@ module Psych
         if string.match?(/\A[-+]?\.\Z/)
           string
         else
-          Float(string.gsub(/[,_]|\.([Ee]|$)/, '\1'))
+          Float(string.delete(',_').gsub(/\.([Ee]|$)/, '\1'))
         end
       elsif string.match?(integer_regex)
         parse_int string
@@ -107,7 +107,7 @@ module Psych
     ###
     # Parse and return an int from +string+
     def parse_int string
-      Integer(string.gsub(/[,_]/, ''))
+      Integer(string.delete(',_'))
     end
 
     ###