Ruby and strings

Strings are just one of the data types supported by Ruby. Like other UNIX world script languages, strings in Ruby could be delimited by double-quotes (“…”) or single-quotes (‘…’), with different meanings.

Double-quotes, are used when we need complex evaluations

(interpolation), on string contents, or scape codes substitution, like \t to tab and \n to new line, and any one expression delimited by #{}.

The same is not possible when single-quotes are used, which only admits some basic substitutions, like \’ and \\, that allow the use of the ‘ and \ characters on string.

Another option to delimit strings is using %q/string/, meaning the same as single-quotes, but no substitution at all, and %Q/string/, meaning the same as double-quotes.

The “/” delimiter could be replaced by any non alpha-numeric character with the same behavior, like: %q(string), or %Q@string@. This flexibility, let you keep a clean code, according with the characters composing your string.

Strings could be defined, across more then one line, with no problem.

Strings are objects (instances), from String class.

# p002e.rb
msg = 'attention! '
puts "msg: #{msg +  msg}"
"#{ 3.times do ; puts 'bye!' end }"
puts %Q|This way equals to " \nbut we can have ' too.|
puts %q[And this one equals to \' and don't replace a\ny\thing]
puts %Q@Now with some subs\ti\tutio\ns@
puts '==============='
puts "#{msg * 3}"
puts 'Here \t we have, sandwiches \n from Tob\'s \\ McCarty\'s'
longo = 'One string, could
start on one line and
end on another'
puts longo
puts "Here \t we have, sandwiches\nfrom Flash \\ Zebra\'s"
puts 'Now we have a "special" word'
puts 'Who am I ?'.class
puts '==============='
puts 'What I can do ?'.methods
puts '==============='