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---
title: strings.FindRESubmatch
description: Returns a slice of all successive matches of the regular expression. Each element is a slice of strings holding the text of the leftmost match of the regular expression and the matches, if any, of its subexpressions.
categories: []
keywords: []
action:
aliases: [findRESubmatch]
related:
- functions/strings/FindRE
- functions/strings/Replace
- functions/strings/ReplaceRE
returnType: '[]string'
signatures: ['strings.FindRESubmatch PATTERN INPUT [LIMIT]']
aliases: [/functions/findresubmatch]
---
By default, `findRESubmatch` finds all matches. You can limit the number of matches with an optional LIMIT argument. A return value of nil indicates no match.
{{% include "functions/_common/regular-expressions.md" %}}
## Demonstrative examples
```go-html-template
{{ findRESubmatch `a(x*)b` "-ab-" }} → [["ab" ""]]
{{ findRESubmatch `a(x*)b` "-axxb-" }} → [["axxb" "xx"]]
{{ findRESubmatch `a(x*)b` "-ab-axb-" }} → [["ab" ""] ["axb" "x"]]
{{ findRESubmatch `a(x*)b` "-axxb-ab-" }} → [["axxb" "xx"] ["ab" ""]]
{{ findRESubmatch `a(x*)b` "-axxb-ab-" 1 }} → [["axxb" "xx"]]
```
## Practical example
This markdown:
```text
- [Example](https://example.org)
- [Hugo](https://gohugo.io)
```
Produces this HTML:
```html
<ul>
<li><a href="https://example.org">Example</a></li>
<li><a href="https://gohugo.io">Hugo</a></li>
</ul>
```
To match the anchor elements, capturing the link destination and text:
```go-html-template
{{ $regex := `<a\s*href="(.+?)">(.+?)</a>` }}
{{ $matches := findRESubmatch $regex .Content }}
```
Viewed as JSON, the data structure of `$matches` in the code above is:
```json
[
[
"<a href=\"https://example.org\"></a>Example</a>",
"https://example.org",
"Example"
],
[
"<a href=\"https://gohugo.io\">Hugo</a>",
"https://gohugo.io",
"Hugo"
]
]
```
To render the `href` attributes:
```go-html-template
{{ range $matches }}
{{ index . 1 }}
{{ end }}
```
Result:
```text
https://example.org
https://gohugo.io
```
{{% note %}}
You can write and test your regular expression using [regex101.com](https://regex101.com/). Be sure to select the Go flavor before you begin.
{{% /note %}}
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