docs: function(node) {
      if (node.type !== 'AssignmentExpression') return false;
  
      return node.left.type === 'MemberExpression' &&
        node.left.object.type === 'Identifier' && node.left.object.name === 'module' &&
        node.left.property.type === 'Identifier' && node.left.property.name === 'exports';
      // TODO: detect module.exports.foo = (or exports.foo =) property assignments, non-default exports
    }