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Ruby字符串插值相当于python';s.format()_Ruby_String_String Interpolation_Language Comparisons - Fatal编程技术网

Ruby字符串插值相当于python';s.format()

Ruby字符串插值相当于python';s.format(),ruby,string,string-interpolation,language-comparisons,Ruby,String,String Interpolation,Language Comparisons,用python我可以 _str = "My name is {}" ... _str = _str.format("Name") 当我尝试时,用红宝石 _str = "My name is #{name}" 解释器抱怨变量name未定义,因此需要 _str = "My name is #{name}" => {name =: "Name"} 如何在ruby中使用字符串占位符供以后使用?您可以使用延迟插值 str = "My name is %{name}" # => "My n

用python我可以

_str = "My name is {}"
...
_str = _str.format("Name")
当我尝试时,用红宝石

_str = "My name is #{name}"
解释器抱怨变量name未定义,因此需要

_str = "My name is #{name}" => {name =: "Name"}

如何在ruby中使用字符串占位符供以后使用?

您可以使用延迟插值

str = "My name is %{name}"
# => "My name is %{name}"

puts str % {name: "Sam"}
# => "My name is Sam"

Ruby中的%{}和%运算符允许将字符串插值延迟到以后。%{}在字符串中定义命名占位符,%将给定的输入绑定到占位符中。

解释器不需要散列,它需要名为
name
的变量

name = "Sam"
p str = "My name is #{name}" # => "My name is Sam"
%方法可以用作@rastasheep。它可以以更简单的方式使用:

str = "My name is %s"
p str % "Name" # => "My name is Name"

基于前面的答案,为了简单和灵活,您可以使用%s代替{}。如果有多个未命名的占位符,请使用数组而不是字符串

_str = "%s is a %s %s"
...
_str % %w(That nice movie)  # => "That is a nice movie"