styled-ax

styled-components theme accessor

Overview

styled-ax (short for accessor) creates a theme property accessor for styled-components. It supports easy access of top level and nested object keys on a theme, as well as a simple interface for piping the accessed values through a chain of functions.

Usage

First you'll need to create a theme and pass it to styled-components ThemeProvider as you normally would.

styled-ax supports the following theme structure:

// theme.js
export default {
  // top level keys
  subtle: `floralwhite`,

  // and/or single level deep objects
  color: {
    subtle: `antiquewhite`
  }
}

Next, create your accessor, passing in your theme:

import styledAx from 'styled-ax'
// or `const styledAx = require(`styled-ax`).default`
import theme from './theme'

const ax = styledAx(theme)
export default ax

Or if running in browser:

<script src="./node_modules/styled-ax/dist/styled-ax.min.js"></script>
<script>
const theme = { /* ... */ }
const ax  = window.styledAx.default(theme)
</script>

Now, instead of default theme usage, where we

color: ${props => props.theme.subtle};

You can

color: ${ax(`subtle`)};

Or if subtle is a property of a color object on your theme (like in the above example), you can

const { color } = ax

const SubtleP = styled.p`
  color: ${color(`subtle`)};
`

Note that color above is just an example - you can call your keys and nested objects whatever you want

Asking for multiple values will return them joined:

// theme = { a: `1px`, b: `2px` }
`margin: ${ax(`a`, `b`)};`
// => margin: 1px 2px;

... unless they are passed to a function, which will receive the values spread

`margin: ${ax(`a`, `b`)(stripUnit)}em`
// stripUnit would be called as stripUnit(`1px`, `2px`)

which brings us to...

Functions

Accessors can take an optional spread of functions to operate on accessed values. The functions form a left to right pipeline, where the first function is passed a spread of the accessed theme values in order, and the following operate on the result:

color: ${color(`primary`, `secondary`)(mix(0.5), darken)};

The mix and darken functions in the example could be implemented with chroma-js

import chroma from 'chroma-js'

export const darken = color => chroma(color).darken(1)

// if your function accepts parameters, use partial application
export const mix = amount => (color1, color2) => chroma.mix(color1, color2, amount)

Tips

Export nested key accessors

At styled-ax creation time, you should export all the functions that reference nested keys for greater readability:

// my-ax.js
const theme = { color: {}, font: {}, size: {}, media: {} }

const ax = styledAx(theme)

export default ax
export const color = ax.color
export const font = ax.font
export const size = ax.size
export const media = ax.media

then you can

import { color, media } from './my-ax'

Conditionals

An accessor accepts values and returns a function that expecting props, so if you need some conditional based on props, you can pass them into ax manually

`color: ${props => ax.color(props.active ? `active` : `default`)(props)};`

Even better, as that's pretty awkward, you can use styled-ax along with ifProp from styled-tools!

`color: ${ifProp(`active`, ax.color(`active`), ax.color(`default`))}`

Install

yarn add styled-ax

npm i styled-ax

License MIT