Q:

Why am I unable to call this method inside of Javascript Aframe.registerComponent?

I am trying to pause the rendering of an a-entity with a custom function that utilizes the .pause() method. Here is my Aframe component:
<body style="margin : 0px; overflow: hidden;">
<script>
  AFRAME.registerComponent('intro', {

    schema: {
      array: { type: "array", default: ["Hi! I'm Ducky and welcome to", "Black", "Duck"] }
    },

    init: function() {
      const self = this;
      pauseTextRender(self);
    }

    function pauseTextRender(component) {
      component.pause();
    }  
 });
</script>
</body>

This is bare minimum. When I check the console I get the error Uncaught SyntaxError: Unexpected token function. I'm not too familiar with Javascript but how can I make an acceptable function for the Aframe class?

A:

Your Javascript Syntax is incorrect. Which is why you are getting the syntax error. Try doing something like this:
,
/**
 * Setup fade-in + fade-out.
 */
setupFadeAnimation: function() {
  var data = this.data;
  var targetEl = this.data.target;

  // Only set up once.
  if (targetEl.dataset.setImageFadeSetup) {
    return;
  }
  targetEl.dataset.setImageFadeSetup = true;

  // Create animation.
  targetEl.setAttribute('animation__fade', {
    property: 'material.color',
    startEvents: 'set-image-fade',
    dir: 'alternate',
    dur: 500,
    from: '#FFF',
    to: '#000'
  });
}

Notice the comma which would be after your init function and the way I declare the function setupFadeAnimation. 

