KittyKittyMewMew

KittyKittyMewMew is a language created by user:ryanninjasheep to be as easy to make a cat program in as possible.

Programs in KittyKittyMewMew

Cat programs are the only possible thing you can make in KittyKittyMewMew. The code is quite simple.

MEOW

This code will output anything that is given as an input.

Interpreters for KittyKittyMewMew

They're really easy to make.

Ruby

C = {/M/ => "pu",/O/ => ' g',%r,W, => "ets",/E/=>%%ts%,/.*[^OpuWtMsEge\t \n]/=>"puts 'invalid code'#"}
def run_code code
  eval(C.to_a.inject(code){|x,y| x.gsub y[0],y[1]})
end

Python 3

class StupidPersonError(Exception):
    pass

alphys  = input()
if alphys != "MEOW":
    raise StupidPersonError("That's not right")
 
print(input())

Shorter one:

print(input() if input()=='MEOW' else 'Invalid code')