语法糖（1）

[].each(&:name)  ->  [].each{|e|e.name}

 

add = lambda{|a,b| a + b}

add.call(1,2) # => 3

also:

add[1,2] # => 3

 

collection.each {|x| puts x}

also:

print_me = lambda{|x| puts x}

collection.each(&print_me)

 

>> Hash[1,2,3,4,5,6]
=> {5=>6, 1=>2, 3=>4}