No increment operator (++) in Ruby?

Skizit picture Skizit · Sep 15, 2010 · Viewed 172.9k times · Source

Possible Duplicate:
Why doesn't Ruby support i++ or i— for fixnum?

Why is there no increment operator in Ruby?

e.g.

i++
++i

Is the ++ operator used for something else? Is there a real reason for this?

Answer

Dave picture Dave · Sep 15, 2010

Ruby has no pre/post increment/decrement operator. For instance, x++ or x-- will fail to parse. More importantly, ++x or --x will do nothing! In fact, they behave as multiple unary prefix operators: -x == ---x == -----x == ...... To increment a number, simply write x += 1.

Taken from "Things That Newcomers to Ruby Should Know " (archive, mirror)

That explains it better than I ever could.

EDIT: and the reason from the language author himself (source):

  1. ++ and -- are NOT reserved operator in Ruby.
  2. C's increment/decrement operators are in fact hidden assignment. They affect variables, not objects. You cannot accomplish assignment via method. Ruby uses +=/-= operator instead.
  3. self cannot be a target of assignment. In addition, altering the value of integer 1 might cause severe confusion throughout the program.