Crate anycase

💼 A case conversion library for Rust.

🚀 Getting started

First, add the anycase crate to your Cargo manifest.

cargo add anycase

Then you can use the as_<case> function to get a Display type.

let s = format!("snake case: {}", anycase::as_snake("Hello world!"));
assert_eq!(s, "snake case: hello_world");

Alternatively, you can use the to_<case> function to get a String.

let s = anycase::to_snake("Hello world!");
assert_eq!(s, "hello_world");

🤸 Usage

The anycase crate provides a set of functions to convert strings between different case styles. The following cases are available.

Given an input of Hello world!:

• as_camel displays helloWorld
• as_pascal displays HelloWorld
• as_snake displays hello_world
• as_screaming_snake displays HELLO_WORLD
• as_kebab displays hello-world
• as_screaming_kebab displays HELLO_WORLD
• as_train displays Hello-World
• as_lower displays hello world
• as_title displays Hello World
• as_upper displays HELLO WORLD

For all of the above functions, you can use the to_<case> variant to get a String instead of a Display type.

Additionally, the crate provides the raw module containing the raw functions which can be used to implement custom case conversion functions.

use anycase::raw;

let input = "Hello world!";
let output =  raw::to_string(input, raw::write_upper, raw::delim_fn("."));
assert_eq!(output, "HELLO.WORLD");

See the module level documentation for more details.

How does it work?

This implementation divides the input string into words and applies a “word function” to each word and calls a “delimiter function” for each word boundary (the space between words).

Word boundaries are defined as follows:

• A set of consecutive 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.

The following char methods are used in the above conditions:

• char::is_alphanumeric is used to determine if a character is a letter/number/symbol
• char::is_lowercase is used to determine if a character is a lowercase letter
• char::is_uppercase is used to determine if a character is an uppercase letter

Features

This crate is designed to be no_std compatible. This is made possible by disabling all default features. The following features are available:

• std (enabled by default) — Currently only enables the alloc feature but is here to allow for forward compatibility with any std-only features.

• alloc — Links the alloc crate and enables the use of String functions.

MSRV

The minimum supported Rust version (MSRV) is 1.56.0. The policy of this crate is to only increase the MSRV in a breaking release.

Modules

raw

This module provides raw functions for transforming strings into different cases. It is used by the functions in the root of this crate.

Functions

as_camel

Display a string as ‘camelCase’.

as_kebab

Display a string as ‘kebab-case’.

as_lower

Display a string as ‘lower case’.

as_pascal

Display a string as ‘PascalCase’.

as_screaming_kebab

Display a string as ‘SCREAMING-KEBAB-CASE’.

as_screaming_snake

Display a string as ‘SCREAMING_SNAKE_CASE’.

as_snake

Display a string as ‘snake_case’.

as_title

Display a string as ‘Title Case’.

as_train

Display a string as ‘Train-Case’.

as_upper

Display a string as ‘UPPER CASE’.

to_camelalloc

Transforms a string to ‘camelCase’.

to_kebaballoc

Transforms a string to ‘kebab-case’.

to_loweralloc

Transforms a string to ‘lower case’.

to_pascalalloc

Transforms a string to ‘PascalCase’.

to_screaming_kebaballoc

Transforms a string to ‘SCREAMING-KEBAB-CASE’.

to_screaming_snakealloc

Transforms a string to ‘SCREAMING_SNAKE_CASE’.

to_snakealloc

Transforms a string to ‘snake_case’.

to_titlealloc

Transforms a string to ‘Title Case’.

to_trainalloc

Transforms a string to ‘Train-Case’.

to_upperalloc

Transforms a string to ‘UPPER CASE’.