PostCSS Stepped Value Functions [][PostCSS]

npm install @csstools/postcss-stepped-value-functions --save-dev

[PostCSS Stepped Value Functions] lets you use round, rem and mod stepped value functions, following the [CSS Values 4] specification.

``css
.test-functions {
padding: 8px mod(18px, 5px) 1px calc(rem(15px, 6px) + 50%);
transform: rotate(mod(-140deg, -90deg));
top: round(15px, 4px);
right: round(nearest, 15px, 4px);
bottom: round(up, 15px, 7px);
left: round(down, 15px, 4px);
width: round(to-zero, 15px, 4px);
}

/ becomes /

.test-functions {
padding: 8px 3px 1px calc(3px + 50%);
transform: rotate(-50deg);
top: 16px;
right: 16px;
bottom: 21px;
left: 12px;
width: 12px;
}
`

Usage

Add [PostCSS Stepped Value Functions] to your project:

`bash
npm install postcss @csstools/postcss-stepped-value-functions --save-dev
`

Use it as a [PostCSS] plugin:

`js
const postcss = require('postcss');
const postcssSteppedValueFunctions = require('@csstools/postcss-stepped-value-functions');

postcss([
postcssSteppedValueFunctions(/ pluginOptions /)
]).process(YOUR_CSS /, processOptions /);
`

⚠️ About custom properties

Given the dynamic nature of custom properties it's impossible to know what the variable value is, which means the plugin can't compute a final value for the stylesheet.

Because of that, any usage that contains a var is skipped.

Options

$3

The preserve option determines whether the original notation
is preserved. By default, it is not preserved.

`js
postcssSteppedValueFunctions({ preserve: true })
`

`css
.test-functions {
padding: 8px mod(18px, 5px) 1px calc(rem(15px, 6px) + 50%);
transform: rotate(mod(-140deg, -90deg));
top: round(15px, 4px);
right: round(nearest, 15px, 4px);
bottom: round(up, 15px, 7px);
left: round(down, 15px, 4px);
width: round(to-zero, 15px, 4px);
}

/ becomes /

.test-functions {
padding: 8px 3px 1px calc(3px + 50%);
padding: 8px mod(18px, 5px) 1px calc(rem(15px, 6px) + 50%);
transform: rotate(-50deg);
transform: rotate(mod(-140deg, -90deg));
top: 16px;
top: round(15px, 4px);
right: 16px;
right: round(nearest, 15px, 4px);
bottom: 21px;
bottom: round(up, 15px, 7px);
left: 12px;
left: round(down, 15px, 4px);
width: 12px;
width: round(to-zero, 15px, 4px);
}
``

[cli-url]: https://github.com/csstools/postcss-plugins/actions/workflows/test.yml?query=workflow/test
[css-url]: https://cssdb.org/#stepped-value-functions
[discord]: https://discord.gg/bUadyRwkJS
[npm-url]: https://www.npmjs.com/package/@csstools/postcss-stepped-value-functions

[PostCSS]: https://github.com/postcss/postcss
[PostCSS Stepped Value Functions]: https://github.com/csstools/postcss-plugins/tree/main/plugins/postcss-stepped-value-functions
[CSS Values 4]: https://www.w3.org/TR/css-values-4/#round-func