arrays - 另一个数组中字符串长度的数组

Question

我需要一个数组来列出不同数组中每个元素的字母数:

words = ["first", "second", "third", "fourth"]

我试图为每个元素的长度创建一个变量。这:

first = words[0].length
second = words[1].length
third = words[2].length
fourth = words[3].length
letters = [first, second, third, fourth]
puts "#{words}"
puts "#{letters}"
puts "first has #{first} characters."
puts "second has #{second} characters."
puts "third has #{third} characters."
puts "fourth has #{fourth} characters."

输出:

["first", "second", "third", "fourth"]
[5, 6, 5, 6]
first has 5 characters.
second has 6 characters.
third has 5 characters.
fourth has 6 characters.

但这似乎是一种低效的做事方式。有没有更强大的方法来做到这一点？

Answer 1

跳过字长数组并使用Array#each :

words.each { |word| puts "#{word} has #{word.size} letters" }
#first has 5 letters
#second has 6 letters
#third has 5 letters
#fourth has 6 letters

如果出于某种原因您仍然需要字长数组，请使用 Array#map :

words.map(&:size) #=> [5, 6, 5, 6]