docs-v2/content/flux/v0/stdlib/strings/trimleft.md

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---
title: strings.trimLeft() function
description: >
`strings.trimLeft()` removes specified leading characters from a string.
menu:
flux_v0_ref:
name: strings.trimLeft
parent: strings
identifier: strings/trimLeft
weight: 101
---
<!------------------------------------------------------------------------------
IMPORTANT: This page was generated from comments in the Flux source code. Any
edits made directly to this page will be overwritten the next time the
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To make updates to this documentation, update the function comments above the
function definition in the Flux source code:
https://github.com/influxdata/flux/blob/master/stdlib/strings/strings.flux#L210-L210
Contributing to Flux: https://github.com/influxdata/flux#contributing
Fluxdoc syntax: https://github.com/influxdata/flux/blob/master/docs/fluxdoc.md
------------------------------------------------------------------------------->
`strings.trimLeft()` removes specified leading characters from a string.
##### Function type signature
```js
(cutset: string, v: string) => string
```
{{% caption %}}
For more information, see [Function type signatures](/flux/v0/function-type-signatures/).
{{% /caption %}}
## Parameters
### v
({{< req >}})
String to to remove characters from.
### cutset
({{< req >}})
Leading characters to trim from the string.
## Examples
### Trim leading periods from all values in a column
```js
import "strings"
data
|> map(fn: (r) => ({r with _value: strings.trimLeft(v: r._value, cutset: ".")}))
```
{{< expand-wrapper >}}
{{% expand "View example input and output" %}}
#### Input data
| _time | _value | *tag |
| -------------------- | -------------- | ---- |
| 2021-01-01T00:00:00Z | ...smpl_g9qczs | t1 |
| 2021-01-01T00:00:10Z | ...smpl_0mgv9n | t1 |
| 2021-01-01T00:00:20Z | ...smpl_phw664 | t1 |
| 2021-01-01T00:00:30Z | ...smpl_guvzy4 | t1 |
| 2021-01-01T00:00:40Z | ...smpl_5v3cce | t1 |
| 2021-01-01T00:00:50Z | ...smpl_s9fmgy | t1 |
| _time | _value | *tag |
| -------------------- | -------------- | ---- |
| 2021-01-01T00:00:00Z | ...smpl_b5eida | t2 |
| 2021-01-01T00:00:10Z | ...smpl_eu4oxp | t2 |
| 2021-01-01T00:00:20Z | ...smpl_5g7tz4 | t2 |
| 2021-01-01T00:00:30Z | ...smpl_sox1ut | t2 |
| 2021-01-01T00:00:40Z | ...smpl_wfm757 | t2 |
| 2021-01-01T00:00:50Z | ...smpl_dtn2bv | t2 |
#### Output data
| _time | _value | *tag |
| -------------------- | ----------- | ---- |
| 2021-01-01T00:00:00Z | smpl_g9qczs | t1 |
| 2021-01-01T00:00:10Z | smpl_0mgv9n | t1 |
| 2021-01-01T00:00:20Z | smpl_phw664 | t1 |
| 2021-01-01T00:00:30Z | smpl_guvzy4 | t1 |
| 2021-01-01T00:00:40Z | smpl_5v3cce | t1 |
| 2021-01-01T00:00:50Z | smpl_s9fmgy | t1 |
| _time | _value | *tag |
| -------------------- | ----------- | ---- |
| 2021-01-01T00:00:00Z | smpl_b5eida | t2 |
| 2021-01-01T00:00:10Z | smpl_eu4oxp | t2 |
| 2021-01-01T00:00:20Z | smpl_5g7tz4 | t2 |
| 2021-01-01T00:00:30Z | smpl_sox1ut | t2 |
| 2021-01-01T00:00:40Z | smpl_wfm757 | t2 |
| 2021-01-01T00:00:50Z | smpl_dtn2bv | t2 |
{{% /expand %}}
{{< /expand-wrapper >}}