Ruby中的多行注释？

Question

如何在Ruby中注释多行？

Answer 1

#!/usr/bin/env ruby

=begin
Every body mentioned this way
to have multiline comments.

The =begin and =end must be at the beginning of the line or
it will be a syntax error.
=end

puts "Hello world!"

<<-DOC
Also, you could create a docstring.
which...
DOC

puts "Hello world!"

"..is kinda ugly and creates
a String instance, but I know one guy
with a Smalltalk background, who
does this."

puts "Hello world!"

##
# most
# people
# do
# this


__END__

But all forgot there is another option.
Only at the end of a file, of course.

• 这就是它的外观（通过截图） - 否则很难解释上述评论的外观。 点击放大：

Answer 2

=begin
My 
multiline
comment
here
=end

Answer 3

尽管存在=begin和=end，但正常且更正确的评论方式是在每一行使用#。如果您阅读任何ruby库的源代码，您会发现这几乎是所有情况下多线注释的完成方式。

Answer 4

#!/usr/bin/env ruby

=begin
Between =begin and =end, any number
of lines may be written. All of these
lines are ignored by the Ruby interpreter.
=end

puts "Hello world!"

Answer 5

使用：

=begin
This
is
a
comment
block
=end

或

# This
# is
# a
# comment
# block

是rdoc当前支持的唯一两个，这是我认为只使用这些的一个很好的理由。

Answer 6

=begin
(some code here)
=end

和

# This code
# on multiple lines
# is commented out

都是正确的。第一种评论的优点是可编辑性 - 它更容易取消注释，因为删除的字符越少。第二种注释的优点是可读性 - 逐行读取代码，更容易判断特定行已被注释掉。你的电话，但想想谁跟你在一起，以及他们阅读和维护是多么容易。

Answer 7

以下是一个例子：

=begin 
print "Give me a number:"
number = gets.chomp.to_f

total = number * 10
puts  "The total value is : #{total}"

=end

您放在=begin和=end之间的所有内容都将被视为评论，无论其中包含多少行代码。

注意：确保=和begin之间没有空格：

• 正确：=begin
• 错误：= begin

Answer 8

=begin comment line 1 comment line 2 =end 确保= begin和= end是该行的第一件事（无空格）

Answer 9

如果有人正在寻找在Ruby on Rails中对html模板中的多行进行注释的方法，那么可能存在= begin = end的问题，例如：

<%
=begin
%>
  ... multiple HTML lines to comment out
  <%= image_tag("image.jpg") %>
<%
=end
%>

由于％＆gt;

将失败关闭image_tag。

在这种情况下，也许可以说这是否是评论，但我更喜欢用“if false”块封闭不受欢迎的部分：

<% if false %>
  ... multiple HTML lines to comment out
  <%= image_tag("image.jpg") %>
<% end %>

这样可行。

Answer 10

  def idle
    <<~aid
    This is some description of what idle does.

    It does nothing actually, it's just here to show an example of multiline
    documentation. Thus said, this is something that is more common in the
    python community. That's an important point as it's good to also fit the
    expectation of your community of work. Now, if you agree with your team to
    go with a solution like this one for documenting your own base code, that's
    fine: just discuss about it with them first.

    Depending on your editor configuration, it won't be colored like a comment,
    like those starting with a "#". But as any keyword can be used for wrapping
    an heredoc, it is easy to spot anyway. One could even come with separated
    words for different puposes, so selective extraction for different types of
    documentation generation would be more practical. Depending on your editor,
    you possibly could configure it to use the same syntax highlight used for
    monoline comment when the keyword is one like aid or whatever you like.

    Also note that the squiggly-heredoc, using "~", allow to position
    the closing term with a level of indentation. That avoids to break the visual reading flow, unlike this far too long line.
    aid
  end

请注意，在发布本文时，stackoverflow引擎无法正确呈现语法颜色。作为练习，在您选择的编辑器中测试它的呈现方式。 ;）