Basic question.
Instead of adding '\n' between the elements:
>> puts "#{[1, 2, 3].join('\n')}"
1\n2\n3
I need to actually add the line feed character, so the output I expect when printing it would be:
1
2
3
What'开发者_如何学运维s the best way to do that in Ruby?
You need to use double quotes.
puts "#{[1, 2, 3].join("\n")}"
Note that you don't have to escape the double quotes because they're within the {}
of a substitution, and thus will not be treated as delimiters for the outer string.
However, you also don't even need the #{}
wrapper if that's all your doing - the following will work fine:
puts [1,2,3].join("\n")
Escaped characters can only be used in double quoted strings:
puts "#{[1, 2, 3].join("\n")}"
But since all you output is this one statement, I wouldn't quote the join
statement:
puts [1, 2, 3].join("\n")
Note that join only adds line feeds between the lines. It will not add a line-feed to the end of the last line. If you need every line to end with a line-feed, then:
#!/usr/bin/ruby1.8
lines = %w(one two three)
s = lines.collect do |line|
line + "\n"
end.join
p s # => "one\ntwo\nthree\n"
print s # => one
# => two
# => three
Ruby doesn't interpret escape sequences in single-quoted strings.
You want to use double-quotes:
puts "#{[1, 2, 3].join(\"\n\")}"
NB: My syntax might be bad - I'm not a Ruby programmer.
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