casex

All in one, self expressive pattern for string case styles

Introduction

casex is a function that applies a case style given a pattern.

Instead of having a specific function for each case style, I provide a self-expressive pattern that represent the desired output. For example, kebab-case can be represented as ca-se and title case as Ca Se.

Install

npm install --save casex

Usage

import { casex } from "casex";

casex({ text: "your text", pattern: "ca-se" }); // your-text

How it works

1. Breaking text into words

By default, casex uses capitalizations (A-Z), -, _ and spaces (\s) to break the text into words.

Let's take for example i_am the-real JohnDoe:

• i: 1st word
• am: 2nd+ word
• the: 2nd+ word
• real: 2nd+ word
• John: 2nd+ word
• Doe: 2nd+ word

1.1 Custom delimiters

The default will likely work for most of your cases, but if you wish, you can provide custom delimiters:

casex({ text: "foo.bar,baz", pattern: "Ca Se", delimiters: ".," }); // Foo Bar Baz

Note: The default delimiters are: `A-Z\s-`.

2. Applying capitalization pattern and gluing words together

Let's take for example Ca_se:

• C: first letter of the first word
• a: second and subsequent letters of the first word
• _: anything between the first two and last two letters is glue and will be repeted between words
• s: first letter of the second and subsequent words
• e: second and subsequent letters of the second and subsequent words

Note: You can use any other letters to describe the pattern, such as aa$aa or `name`. What matters is that it takes the first two and last two letters for checking capitalization and whatever is in the middle is "glue"._

2.1 Special transformations

Besides using lower and uppercase letters, you can also use:

• *: Do not change word
• -: Remove word

Examples

For these examples I'll use the text i_am the-real JohnDoe

lowercase

• Pattern: case
• Output: iamtherealjohndoe

UPPERCASE

• Pattern: CASE
• Output: IAMTHEREALJOHNDOE

snake_case

• Pattern: ca_se
• Output: i_am_the_real_john_doe

spinal-case

• Pattern: ca-se
• Output: i-am-the-real-john-doe

camelCase

• Pattern: caSe
• Output: iAmTheRealJohnDoe

UpperCamelCase

• Pattern: CaSe
• Output: IAmTheRealJohnDoe

Sentence case

• Pattern: Ca se
• Output: I am the real john doe

Title Case

• Pattern: Ca Se
• Output: I Am The Real John Doe

Weird Example

• Pattern: Ca12 34Se
• Output: I12 34Am12 34The12 34Real12 34John12 34Doe

Examples with special characters

Capitalize first letter

• Pattern: C* **
• Output: I am the real John Doe

Initials

• Input: John Doe
• Pattern: C-S-
• Output: JD

Previous versions

Although for most cases it will work just fine, casex 4.x is not fully compatible previous versions. If you need previous docs please refer to:

• v0.x
• v1.x
• v2.x
• v3.x

License

casex is open-sourced software licensed under the MIT License.

4.0.0

• Updated function signature to use named arguments for better clarity
• Use ESM instead of UMD
• Update from default to named export
• Converted from Flow to Typescript

3.0.0

• Added special letters: * and -

2.0.0

• Updated casex to use 'A-Z\\s_-' delimiters instead of accepting only letters and numbers.

1.0.1

• Replaced arrow function with normal function to avoid bundling issues

1.0.0

• Numbers are not treated as lowercase letters
• Fix issue with upper case characters not followed by other characters