4.2 KiB
PostCSS Stepped Value Functions
PostCSS Stepped Value Functions lets you use round
, rem
and mod
stepped value functions, following the CSS Values 4.
.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:
npm install postcss @csstools/postcss-stepped-value-functions --save-dev
Use it as a PostCSS plugin:
const postcss = require('postcss');
const postcssSteppedValueFunctions = require('@csstools/postcss-stepped-value-functions');
postcss([
postcssSteppedValueFunctions(/* pluginOptions */)
]).process(YOUR_CSS /*, processOptions */);
PostCSS Stepped Value Functions runs in all Node environments, with special instructions for:
Node | PostCSS CLI | Webpack | Create React App | Gulp | Grunt |
---|
⚠️ 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
preserve
The preserve
option determines whether the original notation
is preserved. By default, it is not preserved.
postcssSteppedValueFunctions({ preserve: true })
.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);
}
onInvalid
onInvalid
option allows you to assign the warn
value so you can get warnings when the usage of the functions is wrong.
postcssSteppedValueFunctions({ onInvalid: 'warn' })
.invalid {
font-size: mod(18px, 5rem);
}
Will produce on the terminal:
[postcss-stepped-value-functions]: Failed to transform mod(18px, 5rem) as the units don't match