> For the complete documentation index, see [llms.txt](https://chaoses-ib.gitbook.io/directory-opus/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://chaoses-ib.gitbook.io/directory-opus/manual/evaluator/applicable_contexts/rename.md).

# Rename

You can use the evaluator in the [advanced rename](/directory-opus/manual/file_operations/renaming_files/advanced_rename.md) tool to insert text returned by the evaluation.

Use the `{= ... =}` code to insert an evaluation expression. The return value of the expression is inserted into the new filename.

In this evaluation context, the following variables are available:

| Variable      | Type     | Description                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
| ------------- | -------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| *column name* | *varies* | <p>All the <a href="/directory-opus/manual/reference/metadata_keywords/keywords_for_columns.md">column keywords</a> are available as variables in this evaluation context.</p><p>Note that some keywords may use characters like a <code>:</code> that aren't valid in variable names - to access them, use the <a href="/directory-opus/manual/reference/evaluator/val.md">val</a> function.</p><p>Additionally, the <a href="/directory-opus/manual/file_operations/renaming_files/advanced_rename/renaming_with_metadata.md">rename-specific keywords</a> like <strong>parent</strong> and <strong>parentbase</strong> are supported.</p> |
| file\_name    | *string* | Returns the full name of the file the expression is being run for. This may be different from **file** which (as a column keyword), returns the value of the *Name* column (which e.g. may have file extensions hidden).                                                                                                                                                                                                                                                                                                                                                                                                                     |
| is\_dir       | *bool*   | **True** if the expression is being run for a folder, **false** if it's being run for a file.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
| oldname       | *str*    | The value of the "old name" field.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
| newname       | *str*    | The value of the "new name" field.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |

The return value should be a *str* that will be inserted into the new filename.