# Formatter
formatter contains some functions for data formatting.

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## Source:

- [https://github.com/duke-git/lancet/blob/main/formatter/formatter.go](https://github.com/duke-git/lancet/blob/main/formatter/formatter.go)

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## Usage:
```go
import (
    "github.com/duke-git/lancet/v2/formatter"
)
```

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## Index
- [Comma](#Comma)

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## Documentation



### <span id="Comma">Comma</span>
<p>Add comma to a number value by every 3 numbers from right to left. ahead by symbol char. if value is a invalid number string like "aa", return empty string.</p>

<b>Signature:</b>

```go
func Comma[T constraints.Float | constraints.Integer | string](value T, symbol string) string
```
<b>Example:</b>

```go
package main

import (
    "fmt"
    "github.com/duke-git/lancet/v2/formatter"
)

func main() {
    fmt.Println(formatter.Comma("12345", ""))   // "12,345"
    fmt.Println(formatter.Comma(12345.67, "¥")) // "¥12,345.67"
}
```