Columnize is a little Go package that formats strings with separators into columns.

Here’s an example:

package main

import (
    "fmt"

    "github.com/ryanuber/columnize"
)

func main() {
    lines := []string{
        "Name | Type | Country | ABV",
        "Krombacher Pils | Pilsener | Germany | 4.8%",
        "Paulaner Hell | Helles | Germany | 4.9%",
        "Kozel Černý | Dunkel | Czech Republic | 3.8%",
    }
    fmt.Println(columnize.SimpleFormat(lines))
}

Running this program will produce the following output:

Name             Type      Country         ABV
Krombacher Pils  Pilsener  Germany         4.8%
Paulaner Hell    Helles    Germany         4.9%
Kozel Černý      Dunkel    Czech Republic  3.8%

As you can see, it splits string parts separated with | into nicely aligned columns.

You can customize the columnizer by creating a Config and changing its properties:

config := columnize.DefaultConfig()
config.Delim = "|"
config.Glue = "  "
config.Prefix = ""

Instead of SimpleFormat, which uses the default config, call Format, passing it a slice of strings to format and the config you created:

Format(input []string, config *Config) string

That’s it! This package is really easy to use.

Source code and license

GitHub: https://github.com/ryanuber/columnize
Author: Ryan Uber (@ryanuber_)
License: MIT