collatz.py

switch = lambda x: [lambda x: x // 2, lambda x: x * 3 + 1][x % 2](x)

print(switch(5))



~~~


16

collatz.rb

switch = lambda { |x| [lambda { |x| x / 2 }, lambda { |x| x * 3 + 1}][x % 2](x)}

puts switch(5)



~~~
  


collatz.rb:1: syntax error, unexpected '(', expecting '}'
...ambda { |x| x * 3 + 1}][x % 2](x)}
...                               ^
collatz.rb:3: syntax error, unexpected end-of-input, expecting '}'