ruby - Why does passing a method as an argument (&block) not work? -

clock takes block:

def clock(&block)   hours = time.new.hour   puts hours   hours.times     block.call   end end 

this works, , puts "dong" on screen, based on hours of today:

clock   puts "dong..." end 

i'm trying pass dong method:

def dong   puts "dong..." end 

to clock block. this:

clock(dong) 

throws error:

`clock': wrong number of arguments (1 0) (argumenterror) 

can explain why first 1 works, second doesn't? have explicitly define code block you're passing, or can reference method code block?

because

clock(dong) 

doesn't call clock dong method block, calls result of calling dong method. thus, argument error, because try call method (clock) 1 argument, while expected none (except optional block, not count).

to use dong method block in invocation, can do:

clock(&method(:dong)) 

method(:dong) give method object representing dong method (instead of calling it), while & convert proc (and block).