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Why does String#gsub double content?（3个答案）
6天前关闭。
我只是不明白这种行为是否是预期的。
我尝试将字符串中的'字符替换为2个字符\'（基本上是通过在引号之前添加\来转义引号）
我天真的方法是这个str.gsub("'", "\\'")，但我得到了奇怪的结果。我最终使用str.gsub("'") { "\\'" }使它工作，但我想在这里了解gsub的行为。
以下是我尝试的：

str2 = "super'test"
 => "super'test"
str2.gsub("'", "\\'")
 => "supertesttest"                # <==== ??? Where does that comes from ?

# Further tests are to understand if `gsub` behaves as I would expect, and it does...
str2.gsub("'", "")
 => "supertest"
str2.gsub("'", "\\")
 => "super\\test"
str2.gsub("t", "ab")
 => "super'abesab"
str2.gsub("t", "\b")
 => "super'\bes\b"
str2.gsub("t", "\\b")
 => "super'\\bes\\b"
str2.gsub("t", "\'")
 => "super''es'"
str2.gsub("'", "\'")
 => "super'test"
str2.gsub("'", "\\ '")
 => "super\\ 'test"

str2.gsub("'", "\\'")
 => "supertesttest" # I really don't get it....
str2.gsub("'") { "\\'" }
 => "super\\'test" # This works