title: Pass Arguments to Gulpfile Task from Tasks.json?
body: <p>I have a gulpfile task defined which runs node with a javascript file:</p>
  
  <p><div class="snippet" data-lang="js" data-hide="false">
  <div class="snippet-code">
  <pre class="snippet-code-js lang-js prettyprint-override"><code>var exec = require('child_process').exec;
  
  gulp.task('node-run', function (cb) {
    exec('node dest/index.js', function (err, stdout, stderr) {
      console.log(stdout);
      console.log(stderr);
      cb(err);
    });
  })</code></pre>
  </div>
  </div>
  </p>
  
  <p>However, I would like to pass the file name (dest/index.js) as an argument for a task in tasks.json that represents a selected file in VS Code. For example:</p>
  
  <p><div class="snippet" data-lang="js" data-hide="false">
  <div class="snippet-code">
  <pre class="snippet-code-js lang-js prettyprint-override"><code>{
   "version": "0.1.0",
   "command": "gulp",
   "isShellCommand": true,
   "args": [
    "--no-color"
   ],
   "tasks": [
    {
     "taskName": "node-run",
     "showOutput": "always",
     "args": ["${file}"]
    }
   ]
  }</code></pre>
  </div>
  </div>
  </p>
  
  <p>However, when I try executing the task, I receive the following error:</p>
  
  <p><div class="snippet" data-lang="js" data-hide="false">
  <div class="snippet-code">
  <pre class="snippet-code-js lang-js prettyprint-override"><code>Using gulpfile gulpfile.js
  Task '/Users/Tony/Source/HelloVsCode/.vscode/tasks.json' is not in your gulpfile
  Please check the documentation for proper gulpfile formatting</code></pre>
  </div>
  </div>
  </p>
  
  <p>So I'm wondering if it is possible to pass the "${file}" argument to a gulpfile task? </p>