Fun with Nashorn and JRuby

gistfile1.txt

➜  ~  pry
[1] pry(main)> require 'java'
=> false
[2] pry(main)> puts RUBY_PLATFORM; puts RUBY_VERSION
java
1.9.3
=> nil
[3] pry(main)> java_import 'javax.script.ScriptEngineManager'
=> [Java::JavaxScript::ScriptEngineManager]
[4] pry(main)> engine = ScriptEngineManager.new.get_engine_by_name('nashorn')
=> #<Java::JdkNashornApiScripting::NashornScriptEngine:0x2fb3536e>
[5] pry(main)> bindings = engine.create_bindings
=> {}
[6] pry(main)> engine.eval("print(2 + '2');", bindings)
22
=> nil
[7] pry(main)> rc = engine.eval("2 + '2'", bindings)
=> "22"
[8] pry(main)> rc
=> "22"
[9] pry(main)> rc.class
=> String
[10] pry(main)>