I like this literal expression for an array of strings:
%w( i can easily create arrays of words )
I am wondering if there is a literal to get an array of symbols. I know I can do
%w( it is less elegant to create arrays of symbols ).map( &:to_sym )
but it would be so wonderful just to use a literal.
Yes! This is possible now in Ruby 2.0.0. One way to write it is:
%i{foo bar} # => [:foo, :bar]
You can also use other delimiters, so you could also write %i(foo bar)
or %i!foo bar!
for example.
This feature was originally announced here:
http://www.ruby-lang.org/zh_TW/news/2012/11/02/ruby-2-0-0-preview1-released/
It is mentioned in the official documentation of Ruby here:
http://ruby-doc.org/core/doc/syntax/literals_rdoc.html#label-Percent+Strings
In Ruby 1.x, unfortunately the list of available %-delimiters is limited
Modifier Meaning
%q[ ] Non-interpolated String (except for \\ \[ and \])
%Q[ ] Interpolated String (default)
%r[ ] Interpolated Regexp (flags can appear after the closing delimiter)
%s[ ] Non-interpolated Symbol
%w[ ] Non-interpolated Array of words, separated by whitespace
%W[ ] Interpolated Array of words, separated by whitespace
%x[ ] Interpolated shell command
来源:https://stackoverflow.com/questions/8816877/is-there-a-literal-notation-for-an-array-of-symbols