function isExportStatement( node ) {
	var expr;
	var type;

	type = node.type;
	if (
		type === 'ExportAllDeclaration' ||
		type === 'ExportDefaultDeclaration' ||
		type === 'ExportNamedDeclaration'
	) {
		return true;
	}
	if ( type === 'ExpressionStatement' ) {
		expr = node.expression;
		if (
			expr.type === 'AssignmentExpression' &&
			expr.left.type === 'MemberExpression'
		) {
			if (
				expr.left.object.name === 'module' &&
				expr.left.property.name === 'exports'
			) {
				return true;
			}
			if ( expr.left.object.name === 'exports' ) {
				return true;
			}
		}
	}
	return false;
}
Checks whether a node represents an export statement.

@private
@param {ASTNode} node - node to examine
@returns {boolean} boolean indicating whether node represents an export statement