postcss-functions

PostCSS plugin for exposing JavaScript functions.

Installation

npm install --save-dev postcss postcss-functions

Usage

import fs from 'fs';
import postcss from 'postcss';
import functions from 'postcss-functions';
 
const options = {
    //options
};
 
const css = fs.readFileSync('input.css', 'utf8');
 
postcss()
  .use(functions(options))
  .process(css)
  .then((result) => {
    const output = result.css;
  });

Example of a function call:

body {
  prop: foobar();
}

Options

functions

Type: Object

An object containing functions. The function name will correspond with the object key.

Example:

import postcssFunctions from 'postcss-functions';
import { fromString, fromRgb } from 'css-color-converter';

function darken(value, frac) {
  const darken = 1 - parseFloat(frac);
  const rgba = fromString(value).toRgbaArray();
  const r = rgba[0] * darken;
  const g = rgba[1] * darken;
  const b = rgba[2] * darken;
  return fromRgb([r,g,b]).toHexString();
}

postcssFunctions({
  functions: { darken }
});

.foo {
  /* make 10% darker */
  color: darken(blue, 0.1);
}

Hey, what happened to glob?

Versions prior to 4.0.0 had a globbing feature built in, but I've since decided to remove this feature from postcss-functions. This means one less dependency and a smaller package size. For people still interested in this feature, you are free to pair postcss-functions with the globbing library of your choice and pass the imported JavaScript files to the functions option as described above.