code: function getMixin1() {
    const type = NodeType.MixinType;
    const token = tokens[pos];
    const line = token.ln;
    const column = token.col;
    let content = [];
  
    content.push(checkClass(pos) ? getClass() : getShash());
  
    content = content.concat(getSC());
  
    if (checkArguments(pos)) content.push(getArguments());
  
    content = content.concat(getSC());
  
    if (checkBlock(pos)) content.push(getBlock());
  
    return newNode(type, content, line, column);
  }
docs: Get node with a mixin
  @returns {Array} `['mixin', x]`