1,使用迭代器和join的不同
data=['1','2','3']
s=''
data.each{|x| s< puts s puts data.join(" and ") line 4输出的是：1 and 2 and 3 and line 5则是：1 and 2 and 3 可以使用each_with_index实现join data.each_with_index{|x,i| ss< 2,<< pk + 使用前者向string中append时会比后者的性能有所提高，因为后者会创建新的string对象。 3，You want to create a string that contains a representation of a Ruby variable or expression. eg: number=5 puts "the number is #{number}" puts "the number is #{5}" puts "the number now is #{number-1}" puts "the number is #{number.next} or #{number.prior}" 没有Fixnum#prior方法。 Discussion 1）#{}中定义的变量或者类可以在#{}之外使用 puts "Here is #{ class Bar def bar " some text" end end Bar.new.bar}" bar=Bar.new puts bar.bar 输出：Here is some text some text 2）避免#{}的转义作用 foo="foo" puts "##{foo}" puts '#{foo}' puts '#{foo}' puts "#{foo}" puts "#" 3）使用END name = "Mr. Lorum" email = < Dear #{name}, Unfortunately we cannot process your insurance claim at this time. This is because we are a bakery, not an insurance company. Signed,Nil, Null, and None Bakers to Her Majesty the Singleton END puts email 另外END可以用任意的字符替代。 hello=< Does it ok? ok puts hello 这里有一个问题就是END前面不能有空格？ ©著作权归作者所有：来自51CTO博客作者abio的原创作品，如需转载，请注明出处，否则将追究法律责任 职场cookbook休闲Ruby
