cases

A case conversion library for Go.

The currently supported cases are:

Function	Output
cases.ToCamel(s)	camelCase
cases.ToPascal(s)	PascalCase
cases.ToSnake(s)	snake_case
cases.ToScreamingSnake(s)	SCREAMING_SNAKE_CASE
cases.ToKebab(s)	kebab-case
cases.ToScreamingKebab(s)	SCREAMING-KEBAB-CASE
cases.ToTrain(s)	Train-Case
cases.ToLower(s)	lower case
cases.ToTitle(s)	Title Case
cases.ToUpper(s)	UPPER CASE
cases.Transform(s, wordFn, delimFn)	your own case here

Word boundaries are defined as follows:

• A set of consecutive Unicode non-letter/number/symbol e.g. foo _bar is two words (foo and bar)
• A transition from a lowercase letter to an uppercase letter e.g. fooBar is two words (foo and Bar)
• The second last uppercase letter in a word with multiple uppercase letters e.g. FOOBar is two words (FOO and Bar)

Getting started

Install using

go get -u github.com/rossmacarthur/cases

Now convert a string using the relevant function.

import "github.com/rossmacarthur/cases"

cases.ToSnake("XMLHttpRequest") // returns "xml_http_request"

Customizing

This library also exposes a Transform function which allows flexible customization of the output.

For example if you wanted dotted.snake.case you could do the following.

import (
    "strings"
    "github.com/rossmacarthur/cases"
)

func delimDot(s *strings.Builder) {
    s.WriteRune('.')
}

cases.Transform("XmlHttpRequest", cases.ToLower, delimDot) // returns xml.http.request

Here is a more involved example in order to handle acronyms in PascalCase.

import (
    "strings"
    "github.com/rossmacarthur/cases"
)

// The default ToPascal function has no understanding of acronyms
cases.ToPascal("xml_http_request") // returns "XmlHttpRequest"

// We can instead use Transform directly
writeFn := func(s *strings.Builder, word string) {
    w := strings.ToUpper(asLower)
    if w == "XML" || w == "HTTP" {
        s.WriteString(w)
    } else {
        // fallback to default
        cases.WriteTitle(s, word)
    }
}
cases.Transform("xml_http_request", writeFn, nil) // returns "XMLHTTPRequest"

License

This project is distributed under the terms of both the MIT license and the Apache License (Version 2.0).

See LICENSE-APACHE and LICENSE-MIT for details.