> For the complete documentation index, see [llms.txt](https://alexandria.enhe.social/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://alexandria.enhe.social/features/regex-search.md).

# Regex Search

Regex Search, introduced in v1.5, is a power-user feature that lets you use regular expressions as search patterns across all search views in Alexandria: **Omni-Search**, **Search Bookmarks**, and **Search History**.

## Enabling regex mode

Each search view has a small toggle button next to the search input. Click it to switch between normal and regex mode. In regex mode:

* The input border changes color as a visual cue.
* The placeholder text updates to `/pattern/flags` to hint at the expected syntax.

## Writing patterns

Standard JavaScript regex syntax is supported. A few examples:

| Pattern          | What it matches                                  |
| ---------------- | ------------------------------------------------ |
| `github.*issues` | Any URL containing "github" followed by "issues" |
| `/react/i`       | Case-insensitive match for "react"               |
| `^https://news`  | URLs that start with `https://news`              |

Since the Chrome browser APIs don't support regex natively, Alexandria fetches a larger result set (up to 200–500 items) and filters it client-side using JavaScript's `RegExp`.

## Invalid patterns

If you type an invalid regex, Alexandria displays a subtle red **"Invalid regex pattern"** hint below the input instead of crashing. No results will be shown until the pattern is corrected.

## Persisting state

The regex toggle state persists within a session. If you enable it in Omni-Search and navigate to Search History and back, it will remember your preference.


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# Agent Instructions
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## Querying This Documentation
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