Ruby do/end vs braces

Question

Why does this map expression produce different results depending on whether I use braces or do/end?

a = [1,2,3,4,5]


p a.map { |n|
    n*2
}  
#=> [2,4,6         


        

Answer 1

With the do/end syntax you are passing the block to p as a second argument, rather than to the map. You get the same result with:

p a.map

The block is ignored by p as it does not produce anything on inspect.