Ruby 临时变量赋值和修改

Question

我有一个像 "hat" 这样的词，我想造一个完全相同但最后一个字母不同的新词。

word = "hat"
temp = word
temp[temp.length-1] = "d"

puts "temp is #{temp}"
puts "word is #{word}"

# Output:
# temp is had
# word is had

我现在希望 temp = "had" 和 word = "hat" 但是这两个词都变成了 had！

我有一种预感，这可能与指向内存中相同位置的两个变量有关？

为什么会这样，我怎样才能保留这两个值？

Answer 1

Why is this happening

你绝对应该阅读这篇文章 Is Ruby pass by reference or by value?

how can I keep both values?

使用dup。它复制 object

word = "hat"
temp = word.dup
temp[temp.length-1] = "d"

puts "temp is #{temp}"
puts "word is #{word}"

# Output:
# temp is had
# word is hat

Ruby temporary variable assignment and modification