From: Alexey Verkhovsky <alex@...>
Date: 2004-07-17T09:05:08+09:00
Subject: Bug? String literal %s{#{a}} cause irb to abort

irb(main):001:0> s = "#{aaa}"
NameError: undefined local variable or method `aaa' for main:Object
        from (irb):1
        from :0
irb(main):002:0> s = %s{#{aaa}}
/usr/local/lib/ruby/1.9/irb/ruby-token.rb:101:in `Token': undefined
method `ancestors' for nil:NilClass (NoMethodError)
        from /usr/local/lib/ruby/1.9/irb/ruby-lex.rb:995:in
`identify_string'
        from /usr/local/lib/ruby/1.9/irb/ruby-lex.rb:914:in
`identify_quotation'
        from /usr/local/lib/ruby/1.9/irb/ruby-lex.rb:667:in `lex_int2'
        from /usr/local/lib/ruby/1.9/irb/ruby-lex.rb:664:in `call'
        from /usr/local/lib/ruby/1.9/irb/slex.rb:234:in `match_io'
        from /usr/local/lib/ruby/1.9/irb/slex.rb:219:in `match_io'
        from /usr/local/lib/ruby/1.9/irb/slex.rb:73:in `match'
        from /usr/local/lib/ruby/1.9/irb/ruby-lex.rb:277:in `token'
         ... 7 levels...
        from /usr/local/lib/ruby/1.9/irb.rb:70:in `start'
        from /usr/local/lib/ruby/1.9/irb.rb:69:in `catch'
        from /usr/local/lib/ruby/1.9/irb.rb:69:in `start'
        from /usr/local/bin/irb:13
[alex@dhcp-89-2 alex]$ ruby -v
ruby 1.9.0 (2004-07-08) [i686-linux]

------

Meantime, 

[alex@dhcp-89-2 alex]$ ruby
s = %s{#{aaa}}
p s
:"\#{aaa}"