code: function _eval(opts) {
      throwIfRequiredOption(opts, 'src')
  
      var src = opts['src']
  
      // read from stdin
      if (src === 'stdin') {
          readFromStdin(function(src) {
              run(src)
          })
      } else {
          run(src)
      }
  
      function run(src) {
          var fn = new Function('R', ram.compile(src, '<eval>').js)
          fn(R)
      }
  }
docs: executes eval command