Ruby String Translation

Question

I want to find the successor of each element in my encoded string. For example K->M A->C etc.

string.each_char do |ch| 
    dummy_string<< ch.succ.succ
end

However this method translates y->aa.

Is there a method in Ruby that is like maketrans() in Python?

Answer 1

You seem to be looking for String#tr. Use like this: some_string.tr('a-zA-Z', 'c-zabC-ZAB')

Answer 2

I don't know of one offhand, but I think the Ruby way would probably involve passing a block to a regexp function. Here's a dumb one that only works for upper-case letters:

"ABCYZ".gsub(/\w/) { |a| a=="Z" ? "A" : a.succ }
=> "BCDZA"

Edit: meh, never mind, listen to Pesto, he sounds smart.

Answer 3

def successor(s)
    s.tr('a-zA-Z','c-zabC-ZAB')
end

successor("Chris Doggett") #"Ejtku Fqiigvv"