clmconv

README

clmconv

A golang package for converting to spreadsheet column alphabet or integer.

Usage

Default converter

i, err := clmconv.Atoi("A") // i = 0

i := clmconv.MustAtoi("a") // i = 0

a := clmconv.Itoa(0) // a = "A"

Custom converter

converter := clmconv.New(clmconv.WithStartFromOne(), clmconv.WithLowercase())

i, err := converter.Atoi("A") // i = 1

i := converter.MustAtoi("a") // i = 1

a := converter.Itoa(1) // a = "a"

Example

Alphabet	Integer	Integer (WithStartFromOne)
A	0	1
B	1	2
Z	25	26
AA	26	27
ZZ	701	702
ABC	730	731
ABCDE	494264	494265

References

• Blog: Library to convert Spreadsheet column string to integer (Japanese)

Documentation

Overview

Package clmconv converts spreadsheet column alphabet to integer and vice versa.

Example

package main

import (
	"fmt"

	"github.com/takuoki/clmconv"
)

func main() {

	// Default converter
	i, _ := clmconv.Atoi("A")
	a := clmconv.Itoa(0)
	fmt.Printf("i=%d, a='%s'\n", i, a)

	// Custom converter
	converter := clmconv.New(clmconv.WithStartFromOne(), clmconv.WithLowercase())
	i, _ = converter.Atoi("A")
	a = converter.Itoa(1)
	fmt.Printf("i=%d, a='%s'\n", i, a)

}

Output:

i=0, a='A'
i=1, a='a'

Index

• func Atoi(s string) (int, error)
• func Itoa(i int) string
• func MustAtoi(s string) int
• type Converter
  • func New(opts ...Option) *Converter
  • func (c *Converter) Atoi(s string) (int, error)
  • func (c *Converter) Itoa(i int) string
  • func (c *Converter) MustAtoi(s string) int
• type Option
  • func WithLowercase() Option
  • func WithStartFromOne() Option

Examples

• Package
• Atoi
• Itoa
• MustAtoi

Functions

func Atoi

func Atoi(s string) (int, error)

Atoi converts alphabet to number.

Example

package main

import (
	"fmt"

	"github.com/takuoki/clmconv"
)

func main() {
	ai, _ := clmconv.Atoi("A")
	bi, _ := clmconv.Atoi("B")
	_, err := clmconv.Atoi("error!")
	fmt.Printf("ai=%d, bi=%d, err='%v'", ai, bi, err)

}

Output:

ai=0, bi=1, err='must not contain non-alphabetic characters'

func Itoa

func Itoa(i int) string

Itoa converts number to alphabet. If argument is negative, returns empty string.

Example

package main

import (
	"fmt"

	"github.com/takuoki/clmconv"
)

func main() {
	a0 := clmconv.Itoa(0)
	a1 := clmconv.Itoa(1)
	an := clmconv.Itoa(-1)
	fmt.Printf("a0='%s', a1='%s', an='%s'", a0, a1, an)

}

Output:

a0='A', a1='B', an=''

func MustAtoi

func MustAtoi(s string) int

MustAtoi converts alphabet to number. In case of invalid argument, throws panic.

Example

package main

import (
	"fmt"

	"github.com/takuoki/clmconv"
)

func main() {
	ai := clmconv.MustAtoi("A")
	v := func() (v interface{}) {
		defer func() {
			if p := recover(); p != nil {
				v = p
			}
		}()
		clmconv.MustAtoi("panic!")
		return nil
	}()
	fmt.Printf("ai=%d, v='%v'", ai, v)

}

Output:

ai=0, v='must not contain non-alphabetic characters'

Types

type Converter

type Converter struct {
	// contains filtered or unexported fields
}

Converter represents a conversion object. If you need a conversion other than the default, you need create a new conversion object.

func New

func New(opts ...Option) *Converter

New creates a new Converter.

func (*Converter) Atoi

func (c *Converter) Atoi(s string) (int, error)

Atoi converts alphabet to number with converter.

func (*Converter) Itoa

func (c *Converter) Itoa(i int) string

Itoa converts number to alphabet with converter. If argument is negative, returns empty string.

func (*Converter) MustAtoi

func (c *Converter) MustAtoi(s string) int

MustAtoi converts alphabet to number with converter. In case of invalid argument, throws panic.

type Option

type Option interface {
	// contains filtered or unexported methods
}

Option is an option that configures Converter.

func WithLowercase

func WithLowercase() Option

WithLowercase is an option to use lowercase letters as the output alphabet. This option works only with `Itoa`.

func WithStartFromOne

func WithStartFromOne() Option

WithStartFromOne is an option to start the index from one. This option works for both `Atoi` and `Itoa`.