What is the difference between the “sort” and “sort!” method in ruby?
来自Ruby的官方文档：
sort → new_ary sort { |a, b| block } → new_ary Returns a new array
created by sorting self.Comparisons for the sort will be done using the <=> operator or using
an optional code block.The block must implement a comparison between a and b, and return -1,
when a follows b, 0 when a and b are equivalent, or +1 if b follows a.See also Enumerable#sort_by.
1 2 3 | a = ["d","a","e","c","b" ] a.sort #=> ["a","b","c","d","e"] a.sort { |x,y| y <=> x } #=> ["e","d","c","b","a"] |
sort! → ary click to toggle source sort! { |a, b| block } → ary Sorts
self in place.Comparisons for the sort will be done using the <=> operator or using
an optional code block.The block must implement a comparison between a and b, and return -1,
when a follows b, 0 when a and b are equivalent, or +1 if b follows a.See also Enumerable#sort_by.
1 2 3 | a = ["d","a","e","c","b" ] a.sort! #=> ["a","b","c","d","e"] a.sort! { |x,y| y <=> x } #=> ["e","d","c","b","a"] |
结果似乎是一样的，那么有什么区别呢？
1 2 3 | a = [4,3,2,5,1] a.sort # => [1,2,3,4,5] a is still [4,3,2,5,1] |
在哪里
1 2 3 | a = [4,3,2,5,1] a.sort! # => [1,2,3,4,5] a is now [1,2,3,4,5] |
1 2 3 4 5 | '!' is the bang method in ruby, it will replace the existing value ex: .sort is a normal sorting method in ruby .sort! its a bang method in ruby its override the existing value. |
在铁轨上！用于应用更改并更新其调用对象意味着
a.sort只返回排序后的数组，而返回a.sort！将返回已排序的数组，并将新的排序结果保存到变量中。