为什么我所有的看跌期权都返回=> nil? [英] Why are all my puts returning =>nil?

问题描述

我知道这似乎是一个非常简单的问题，但确实困扰我我的看跌期权不断产生"=> nil"，因此我搜寻了一个答案，但找不到答案.谢谢.

I know this may seem like a really simple question, but it really bothers me that my puts keep generating "=> nil" and I scoured for an answer but could not find one. Thanks.

放入闪烁" * 4 眨眼眨眼眨眼眨眼 =>无

puts 'blink ' *4 blink blink blink blink => nil

推荐答案

因为这是puts的返回值:

puts(obj，...)→无

puts(obj, ...) → nil

与IO#print一样，将给定的对象写入ios. 在任何不包含的记录后写一个记录分隔符(通常是换行符) 已经以换行符结尾.如果使用数组参数进行调用， 将每个元素写在新行上.如果不带参数调用 输出单个记录分隔符.

Writes the given objects to ios as with IO#print. Writes a record separator (typically a newline) after any that do not already end with a newline sequence. If called with an array argument, writes each element on a new line. If called without arguments, outputs a single record separator.

来源: http://www.ruby-doc.org/core-1.9.3/IO.html#method-i-puts

此外，我想这只是在irb中吗?因为在常规应用程序中调用puts不会显示其返回值.

Also, I assume this is just in irb? because calling puts doesn't display its return value in normal applications.

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