117 lines
3.1 KiB
Markdown
117 lines
3.1 KiB
Markdown
---
|
|
title: strings.trimPrefix() function
|
|
description: >
|
|
`strings.trimPrefix()` removes a prefix from a string. Strings that do not start with the prefix are returned unchanged.
|
|
menu:
|
|
flux_v0_ref:
|
|
name: strings.trimPrefix
|
|
parent: strings
|
|
identifier: strings/trimPrefix
|
|
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
|
|
documentation is generated.
|
|
|
|
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#L119-L119
|
|
|
|
Contributing to Flux: https://github.com/influxdata/flux#contributing
|
|
Fluxdoc syntax: https://github.com/influxdata/flux/blob/master/docs/fluxdoc.md
|
|
|
|
------------------------------------------------------------------------------->
|
|
|
|
`strings.trimPrefix()` removes a prefix from a string. Strings that do not start with the prefix are returned unchanged.
|
|
|
|
|
|
|
|
##### Function type signature
|
|
|
|
```js
|
|
(prefix: string, v: string) => string
|
|
```
|
|
|
|
{{% caption %}}
|
|
For more information, see [Function type signatures](/flux/v0/function-type-signatures/).
|
|
{{% /caption %}}
|
|
|
|
## Parameters
|
|
|
|
### v
|
|
({{< req >}})
|
|
String to trim.
|
|
|
|
|
|
|
|
### prefix
|
|
({{< req >}})
|
|
Prefix to remove.
|
|
|
|
|
|
|
|
|
|
## Examples
|
|
|
|
### Trim a prefix from all values in a column
|
|
|
|
```js
|
|
import "sampledata"
|
|
import "strings"
|
|
|
|
sampledata.string()
|
|
|> map(fn: (r) => ({r with _value: strings.trimPrefix(v: r._value, prefix: "smpl_")}))
|
|
|
|
```
|
|
|
|
{{< expand-wrapper >}}
|
|
{{% expand "View example input and output" %}}
|
|
|
|
#### Input data
|
|
|
|
| _time | *tag | _value |
|
|
| -------------------- | ---- | ----------- |
|
|
| 2021-01-01T00:00:00Z | t1 | smpl_g9qczs |
|
|
| 2021-01-01T00:00:10Z | t1 | smpl_0mgv9n |
|
|
| 2021-01-01T00:00:20Z | t1 | smpl_phw664 |
|
|
| 2021-01-01T00:00:30Z | t1 | smpl_guvzy4 |
|
|
| 2021-01-01T00:00:40Z | t1 | smpl_5v3cce |
|
|
| 2021-01-01T00:00:50Z | t1 | smpl_s9fmgy |
|
|
|
|
| _time | *tag | _value |
|
|
| -------------------- | ---- | ----------- |
|
|
| 2021-01-01T00:00:00Z | t2 | smpl_b5eida |
|
|
| 2021-01-01T00:00:10Z | t2 | smpl_eu4oxp |
|
|
| 2021-01-01T00:00:20Z | t2 | smpl_5g7tz4 |
|
|
| 2021-01-01T00:00:30Z | t2 | smpl_sox1ut |
|
|
| 2021-01-01T00:00:40Z | t2 | smpl_wfm757 |
|
|
| 2021-01-01T00:00:50Z | t2 | smpl_dtn2bv |
|
|
|
|
|
|
#### Output data
|
|
|
|
| _time | _value | *tag |
|
|
| -------------------- | ------- | ---- |
|
|
| 2021-01-01T00:00:00Z | g9qczs | t1 |
|
|
| 2021-01-01T00:00:10Z | 0mgv9n | t1 |
|
|
| 2021-01-01T00:00:20Z | phw664 | t1 |
|
|
| 2021-01-01T00:00:30Z | guvzy4 | t1 |
|
|
| 2021-01-01T00:00:40Z | 5v3cce | t1 |
|
|
| 2021-01-01T00:00:50Z | s9fmgy | t1 |
|
|
|
|
| _time | _value | *tag |
|
|
| -------------------- | ------- | ---- |
|
|
| 2021-01-01T00:00:00Z | b5eida | t2 |
|
|
| 2021-01-01T00:00:10Z | eu4oxp | t2 |
|
|
| 2021-01-01T00:00:20Z | 5g7tz4 | t2 |
|
|
| 2021-01-01T00:00:30Z | sox1ut | t2 |
|
|
| 2021-01-01T00:00:40Z | wfm757 | t2 |
|
|
| 2021-01-01T00:00:50Z | dtn2bv | t2 |
|
|
|
|
{{% /expand %}}
|
|
{{< /expand-wrapper >}}
|