A loader-agnostic CSS Modules implementation, based on PostCSS
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CSS Module Loader Core

A loader-agnostic CSS Modules implementation, based on PostCSS

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import Core from 'css-modules-loader-core'
let core = new Core()

core.load( sourceString , sourcePath , pathFetcher ) =>
  Promise({ injectableSource, exportTokens })

Processes the input CSS sourceString, looking for dependencies such as @import or :import. Any localisation will happen by prefixing a sanitised version of sourcePath When dependencies are found, it will ask the pathFetcher for each dependency, resolve & inline any imports, and return the following object:

  • injectableSource: the final, merged CSS file without @import or :import statements
  • exportTokens: the mapping from local name to scoped name, as described in the file's :export block

These should map nicely to what your build-tool-specific loader needs to do its job.

new Core([plugins])

The default set of plugins is [postcss-modules-local-by-default, postcss-modules-extract-imports, postcss-modules-scope] (i.e. the CSS Modules specification). This can override which PostCSS plugins you wish to execute, e.g.

import Core from 'css-loader-core'
import autoprefixer from 'autoprefixer'
import colorFunctions from 'postcss-color-function'

// Don't run local-by-default, but use colorFunctions 
// beforehand and autoprefixer afterwards:
let core = new Core([
  autoprefixer("Last 2 Versions")