Function twind

packages/core/src/twind.ts:42–164

(userConfig: TwindConfig<any> | TwindUserConfig<any>, sheet: Sheet)

): Twind<BaseTheme & ExtractThemes<Theme, Presets>, Target>

export function twind(userConfig: TwindConfig<any> | TwindUserConfig<any>, sheet: Sheet): Twind {
  const config = defineConfig(userConfig as TwindUserConfig<any>)

  const context = createContext(config)

  // Map of tokens to generated className
  let cache = new Map<string, string>()

  // An array of precedence by index within the sheet
  // always sorted
  let sortedPrecedences: SortableRule[] = []

  // Cache for already inserted css rules
  // to prevent double insertions
  let insertedRules = new Set<string>()

  sheet.resume(
    (className) => cache.set(className, className),
    (cssText, rule) => {
      sheet.insert(cssText, sortedPrecedences.length, rule)
      sortedPrecedences.push(rule)
      insertedRules.add(cssText)
    },
  )

  function insert(rule: TwindRule): string | undefined {
    const finalRule = context.f(rule)

    const cssText = stringify(finalRule)

    // If not already inserted
    if (cssText && !insertedRules.has(cssText)) {
      // Mark rule as inserted
      insertedRules.add(cssText)

      // Find the correct position
      const index = sortedInsertionIndex(sortedPrecedences, rule)

      // Insert
      sheet.insert(cssText, index, rule)

      // Update sorted index
      sortedPrecedences.splice(index, 0, rule)
    }

    return finalRule.n
  }

  return Object.defineProperties(
    function tw(tokens) {
      if (!cache.size) {
        for (let preflight of asArray(config.preflight)) {
          if (typeof preflight == 'function') {
            preflight = preflight(context)
          }

          if (preflight) {
            ;(typeof preflight == 'string'