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opencloud/vendor/github.com/clipperhouse/displaywidth/README.md
dependabot[bot] 056039b624 build(deps): bump github.com/olekukonko/tablewriter from 1.1.2 to 1.1.3
Bumps [github.com/olekukonko/tablewriter](https://github.com/olekukonko/tablewriter) from 1.1.2 to 1.1.3.
- [Release notes](https://github.com/olekukonko/tablewriter/releases)
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---
updated-dependencies:
- dependency-name: github.com/olekukonko/tablewriter
  dependency-version: 1.1.3
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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2026-01-23 10:16:56 +01:00

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Markdown

# displaywidth
A high-performance Go package for measuring the monospace display width of strings, UTF-8 bytes, and runes.
[![Documentation](https://pkg.go.dev/badge/github.com/clipperhouse/displaywidth.svg)](https://pkg.go.dev/github.com/clipperhouse/displaywidth)
[![Test](https://github.com/clipperhouse/displaywidth/actions/workflows/gotest.yml/badge.svg)](https://github.com/clipperhouse/displaywidth/actions/workflows/gotest.yml)
[![Fuzz](https://github.com/clipperhouse/displaywidth/actions/workflows/gofuzz.yml/badge.svg)](https://github.com/clipperhouse/displaywidth/actions/workflows/gofuzz.yml)
## Install
```bash
go get github.com/clipperhouse/displaywidth
```
## Usage
```go
package main
import (
"fmt"
"github.com/clipperhouse/displaywidth"
)
func main() {
width := displaywidth.String("Hello, 世界!")
fmt.Println(width)
width = displaywidth.Bytes([]byte("🌍"))
fmt.Println(width)
width = displaywidth.Rune('🌍')
fmt.Println(width)
}
```
For most purposes, you should use the `String` or `Bytes` methods. They sum
the widths of grapheme clusters in the string or byte slice.
> Note: in your application, iterating over runes to measure width is likely incorrect;
the smallest unit of display is a grapheme, not a rune.
### Iterating over graphemes
If you need the individual graphemes:
```go
import (
"fmt"
"github.com/clipperhouse/displaywidth"
)
func main() {
g := displaywidth.StringGraphemes("Hello, 世界!")
for g.Next() {
width := g.Width()
value := g.Value()
// do something with the width or value
}
}
```
### Options
There is one option, `displaywidth.Options.EastAsianWidth`, which defines
how [East Asian Ambiguous characters](https://www.unicode.org/reports/tr11/#Ambiguous)
are treated.
When `false` (default), East Asian Ambiguous characters are treated as width 1.
When `true`, they are treated as width 2.
You may wish to configure this based on environment variables or locale.
`go-runewidth`, for example, does so
[during package initialization](https://github.com/mattn/go-runewidth/blob/master/runewidth.go#L26C1-L45C2).
`displaywidth` does not do this automatically, we prefer to leave it to you.
You might do something like:
```go
var width displaywidth.Options // zero value is default
func init() {
if os.Getenv("EAST_ASIAN_WIDTH") == "true" {
width = displaywidth.Options{EastAsianWidth: true}
}
// or check locale, or any other logic you want
}
// use it in your logic
func myApp() {
fmt.Println(width.String("Hello, 世界!"))
}
```
## Technical standards and compatibility
This package implements the Unicode East Asian Width standard
([UAX #11](https://www.unicode.org/reports/tr11/tr11-43.html)), and handles
[version selectors](https://en.wikipedia.org/wiki/Variation_Selectors_(Unicode_block)),
and [regional indicator pairs](https://en.wikipedia.org/wiki/Regional_indicator_symbol)
(flags). We implement [Unicode TR51](https://www.unicode.org/reports/tr51/tr51-27.html). We are keeping
an eye on [emerging standards](https://www.jeffquast.com/post/state-of-terminal-emulation-2025/).
`clipperhouse/displaywidth`, `mattn/go-runewidth`, and `rivo/uniseg` will
give the same outputs for most real-world text. Extensive details are in the
[compatibility analysis](comparison/COMPATIBILITY_ANALYSIS.md).
If you wish to investigate the core logic, see the `lookupProperties` and `width`
functions in [width.go](width.go#L139). The essential trie generation logic is in
`buildPropertyBitmap` in [unicode.go](internal/gen/unicode.go#L316).
## Prior Art
[mattn/go-runewidth](https://github.com/mattn/go-runewidth)
[rivo/uniseg](https://github.com/rivo/uniseg)
[x/text/width](https://pkg.go.dev/golang.org/x/text/width)
[x/text/internal/triegen](https://pkg.go.dev/golang.org/x/text/internal/triegen)
## Benchmarks
```bash
cd comparison
go test -bench=. -benchmem
```
```
goos: darwin
goarch: arm64
pkg: github.com/clipperhouse/displaywidth/comparison
cpu: Apple M2
BenchmarkString_Mixed/clipperhouse/displaywidth-8 10326 ns/op 163.37 MB/s 0 B/op 0 allocs/op
BenchmarkString_Mixed/mattn/go-runewidth-8 14415 ns/op 117.03 MB/s 0 B/op 0 allocs/op
BenchmarkString_Mixed/rivo/uniseg-8 19343 ns/op 87.21 MB/s 0 B/op 0 allocs/op
BenchmarkString_EastAsian/clipperhouse/displaywidth-8 10561 ns/op 159.74 MB/s 0 B/op 0 allocs/op
BenchmarkString_EastAsian/mattn/go-runewidth-8 23790 ns/op 70.91 MB/s 0 B/op 0 allocs/op
BenchmarkString_EastAsian/rivo/uniseg-8 19322 ns/op 87.31 MB/s 0 B/op 0 allocs/op
BenchmarkString_ASCII/clipperhouse/displaywidth-8 1033 ns/op 123.88 MB/s 0 B/op 0 allocs/op
BenchmarkString_ASCII/mattn/go-runewidth-8 1168 ns/op 109.59 MB/s 0 B/op 0 allocs/op
BenchmarkString_ASCII/rivo/uniseg-8 1585 ns/op 80.74 MB/s 0 B/op 0 allocs/op
BenchmarkString_Emoji/clipperhouse/displaywidth-8 3034 ns/op 238.61 MB/s 0 B/op 0 allocs/op
BenchmarkString_Emoji/mattn/go-runewidth-8 4797 ns/op 150.94 MB/s 0 B/op 0 allocs/op
BenchmarkString_Emoji/rivo/uniseg-8 6612 ns/op 109.50 MB/s 0 B/op 0 allocs/op
BenchmarkRune_Mixed/clipperhouse/displaywidth-8 3343 ns/op 504.67 MB/s 0 B/op 0 allocs/op
BenchmarkRune_Mixed/mattn/go-runewidth-8 5414 ns/op 311.62 MB/s 0 B/op 0 allocs/op
BenchmarkRune_EastAsian/clipperhouse/displaywidth-8 3393 ns/op 497.17 MB/s 0 B/op 0 allocs/op
BenchmarkRune_EastAsian/mattn/go-runewidth-8 15312 ns/op 110.17 MB/s 0 B/op 0 allocs/op
BenchmarkRune_ASCII/clipperhouse/displaywidth-8 256.9 ns/op 498.32 MB/s 0 B/op 0 allocs/op
BenchmarkRune_ASCII/mattn/go-runewidth-8 265.7 ns/op 481.75 MB/s 0 B/op 0 allocs/op
BenchmarkRune_Emoji/clipperhouse/displaywidth-8 1336 ns/op 541.96 MB/s 0 B/op 0 allocs/op
BenchmarkRune_Emoji/mattn/go-runewidth-8 2304 ns/op 314.23 MB/s 0 B/op 0 allocs/op
```
Here are some notes on [how to make Unicode things fast](https://clipperhouse.com/go-unicode/).