Incorrect gsub replacement

Question

I am trying to replace all alphanumeric characters of a letter with the character “#” using the gsub method, but Ruby inserts a backslash before the “@” character.

eg:

" [e-mail] ".gsub(/[a-z0-9]/, "#") returns "###\#@###.###" instead of "####@###.###" .

Answer 1

It returns "####@###.###" , as expected, to try:

 puts " [e-mail] ".gsub(/[a-z0-9]/, "#") 

What you see in IRB / Pry is to prevent #@ interpreting as string interpolation.

Please refer to @Stefan's very valuable comment below.

Answer 2

tr faster than gsub :

 puts " [e-mail] ".tr('a-zA-Z0-9', '#') # >> ###@###.###