It's a common joke that Ruby is designed to make it as hard as possible for parsers. For the code samples going forward, keep in mind that in ruby you don't ne

It's a common joke that Ruby is designed to make it as hard as possible for parsers. For the code samples going forward, keep in mind that in ruby you don't need a literal return statement to return a value from a method. Just whatever value is last, is returned: def val 5 end That method would always return 5. > But then if the b() call itself returns a function, then is that function auto-called as well? No, the only way to pass a method is by using method(method_name_here), which returns a Method object. To execute a Method object, you need to call call on it: def a end method(:a).call So if you have a method that returns a method, it should not be automatically called, so there's no loop necessary: def b method(:a) end z = b Then z is a Method object, namely a. Some experiments to answer your questions (I admit I wasn't sure for all of them what the outcome would be). IRB is Ruby's repl: irb(main):001:0> def a irb(main):002:1> 5 irb(main):003:1> end irb(main):019:0> {a: 1} => {:a=>1} irb(main):020:0> {a(): 1} SyntaxError: (irb):20: syntax error, unexpected ':', expecting tASSOC irb(main):009:0> def h(num = 10) irb(main):010:1> num irb(main):011:1> end irb(main):012:0> h => 10 irb(main):013:0> h-3 => 7 irb(main):014:0> h -3 => -3 irb(main):015:0> h - 3 => 7 irb(main):001:0> a?b:c NameError: undefined local variable or method `c' for main:Object