---
title: "ure"
aliases:
    - firmwareapi/micropython/ure.html
    - firmwareapi/micropython/ure.md
    - chapter/firmwareapi/micropython/ure
---

This module implements regular expression operations. Regular expression syntax supported is a subset of CPython re module (and actually is a subset of POSIX extended regular expressions).

Supported operators are:

`.` Match any character. `[]` Match set of characters. Individual characters and ranges are supported.

```text
^
$
?
*
+
??
*?
+?
```

Counted repetitions `({m,n})`, more advanced assertions, named groups, etc. are not supported.

## Methods

#### ure.compile(regex)

Compile regular expression, return `regex object`.

#### ure.match(regex, string)

Match regex against `string`. Match always happens from starting position in a string.

#### ure.search(regex, string)

Search regex in a string. Unlike match, this will search string for first position which matches regex (which still may be 0 if regex is anchored).

#### ure.DEBUG

Flag value, display debug information about compiled expression.

## Regex objects

Compiled regular expression. Instances of this class are created using `ure.compile()`.

#### regex.match(string)

#### regex.search(string)

#### regex.split(string, max\_split=-1)

## Match objects

Match objects as returned by `match()` and `search()` methods.

#### match.group(\[index\])

Only numeric groups are supported.