CX

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cx is a TypeScript utility that contains conditional processing, can process both CSS Module and native CSS className (Inspired by classNames/bind)

cx('a', true, { c: true })
// => 'a c'  just like classNames function

// But when you bind styles in cx and the first argument is arr
import styles from './style.module.css'
import classNames from '@crown3/cx'
const cx = classNames.bind(styles)
cx(['a', { b: true }], 'c', { d: true }, [{ e: true }])
// => 'a-module-class b-module-class c d e

Getting Started

# via npm
npm install @crown3/cx

# or Yarn
yarn add @crown3/cx

Use with TypeScript

import classNames, { CX } from '@crown3/cx'
import styles from './demo.module.css'

const cx: CX = classNames.bind(styles)
cx(['hello'], 'world')
// => 'hello-module-class world'

Or in JavaScript

import { classNames } from '@crown3/cx'
import styles from './demo.module.css'

const cx = classNames.bind(styles)

Documentation

Only when you bind this to CSS Module styles and the first argument is array, cx will handle all arguments in this array as CSS Module (Others are still handled as normal CSS styles)

• Note: If you bind a CSS Module but the first argument isn't array, cx will handle all arguments as normal CSS styles
• The processing logic of the arguments is similar with classNames/bind, all arguments will do a conditionally handle and if the result is true, the key will be output
  • But there's a little different with classNames/bind in handling CSS Module styles, when the class name doesn't exist in the CSS Module, cx will ignore this instead of returning it as a string like classNames/bind

// mock a CSS Module styles
import classNames from '@crown3/cx'

const cx = classNames
cx([{ a: true, b: false }], 'c', undefined, null) // => 'a c'

// But when you bind styles
const styles = { a: 'a1', b: 'b2' }
const cx = classNames.bind(styles)

cx(['a', { b: true }]) // => 'a1 b2'
// But if first arg isn't array, cx will handle all arguments as normal css, even if you bind styles
cx('a', ['b']) // => 'a b'

// the arguments can accept any number of items which can be a string, boolean, number, array or Object
// If the value associated with a given key is falsy, the key won't be included in the output
cx(['a', { b: true }, [{ b: true }, 'c']], 'a', ['b'], [{ c: true }])
// => 'a1 b2 b2 a b c'
// Note: there hasn't 'cx' in our output, because the Module styles doesn't have the 'c' key

// Even using it like this
cx(
  [
    {
      toString() {
        return 'a'
      },
    },
    {
      toString() {
        return 'c'
      },
    },
  ],
  {
    toString() {
      return 'b'
    },
  }
)
// => 'a1 b'

License

@crown3/cx is licensed under a MIT License.