gistfile1.js

var fs = require('fs'), vm = require('vm'), path = require('path'); 
var repl = require('repl'); 
// Add source ability 
repl.REPLServer.prototype.source = function (file) { 
  if (!~file.indexOf('.')) file += '.js'; 
  if (path.existsSync(file)) { 
    vm.runInContext(fs.readFileSync(file).toString(), this.context); 
  } else { 
    this.outputStream.write('ERROR: file not found "' + file + '"\n'); 
  } 
  this.displayPrompt(); 
} 

var server = repl.start(); 
// In REPL "./ file" will source "file.js" 
server.defineCommand('/', { 
  help: 'Source file', 
  action: function (file) { 
    this.source(file); 
  } 
}); 

// From command line arguments 
for (var i = 2; i < process.argv.length; i++) { 
  server.source(process.argv[i]); 
}