不带@的调用实例变量 [英] Calling Instance Variables without @

问题描述

我是Ruby编程的新手，我现在看到了一些示例，在这些示例中调用实例变量时，其前面没有"@"符号.

I'm new to Ruby programming and I've seen a few examples now where an instance variable is being called without the "@" symbol in front of it.

我不确定是否是因为该类中的 attr_reader 导致了方法的调用以及实例变量是否存储在方法中，或者我是否对此有错误的理解实例变量.

I'm not sure if this because the method is being called and the instance variable is stored in the method as a result of a attr_reader in the class or if because I have the wrong understanding of instance variables.

这是我所指的示例，摘自Russ Olsen的雄辩的Ruby，其中 @unique 数组具有调用的 size 方法，而没有"@""前面的符号:

Here's an example of what I'm referring to taken from Russ Olsen's Eloquent Ruby, where the @unique array has the size method called on it without the "@" symbol in front of it:

class TextCompressor
attr_reader :unique, :index

def initialize(text)
    @unique = []
    @index = []
    add_text(text)
end

def add_text(text)
    words = text.split
    words.each { |word| add_word(word) }
end

def add_word(word)
    i = unique_index_of(word) || add_unique_word(word)
    @index << i
end

def unique_index_of(word)
    @unique.index(word)
end

def add_unique_word(word)
    @unique << word
    unique.size - 1
end
end

推荐答案

我也是Ruby的新手，已经学习了几周.我相信:

I'm also new to Ruby and have been learning for a couple weeks. I believe:

attr_reader :unique

在功能上与定义方法相同:

is functionally identical to defining the method:

def unique
  @unique
end

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