return cr
	}
	return r
}

// Variant represents a registered variant of a language as defined by BCP 47.
type Variant struct {
	ID  uint8
	str string
}

// ParseVariant parses and returns a Variant. An error is returned if s is not
// a valid variant.
func ParseVariant(s string) (v Variant, err error) {
	defer func() {
		if recover() != nil {
			v = Variant{}
			err = ErrSyntax
		}
	}()

		if b.private != "" {
			b.extensions = append(b.extensions, b.private)
		}
		n := maxCoreSize + tokenLen(b.variants...) + tokenLen(b.extensions...)
		buf := make([]byte, n)
		p := t.genCoreBytes(buf)
		t.pVariant = byte(p)
		p += appendTokens(buf[p:], b.variants...)
		t.pExt = uint16(p)
		p += appendTokens(buf[p:], b.extensions...)
		t.str = string(buf[:p])
		// We may not always need to remake the string, but when or when not

	if needSort {
		sort.Sort(variantsSort{varID, variant})
		k, l := 0, -1
		for i, v := range varID {
			w := int(v)
			if l == w {
				// Remove duplicates.
				continue
			}
			varID[k] = varID[i]
			variant[k] = variant[i]
			k++
			l = w
		}
		if str := bytes.Join(variant[:k], separator); len(str) == 0 {
			end = start - 1
		} else {
			scan.resizeRange(start, end, len(str))

import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

/**
 * Declares that a property represents a variant dimension. Variants are used in dependency
 * resolution to discriminate between various binaries that may match the requirements (such
 * as a platform, a build type, ...).
 *

  compileTestVariantSwift -> linkTestVariant -> installTestVariant -> xcTestVariant [dir=back, style=dashed]
  compileTestVariantSwift[label=<compile<i>Variant</i>Swift>]
  linkTestVariant[label=<link<i>Variant</i>>]
  installTestVariant[label=<installTest<i>Variant</i>>]
  xcTestVariant[label=<xcTest<i>Variant</i>>]

  rankdir=LR

  compileVariantCpp -> linkVariant -> installVariant -> assembleVariant [dir=back, style=dashed]
  compileVariantCpp[label=<compile<i>Variant</i>Cpp>]
  linkVariant[label=<link<i>Variant</i>>]
  installVariant[label=<install<i>Variant</i>>]
  assembleVariant[label=<assemble<i>Variant</i>>]

  rankdir=LR

  compileVariantSwift -> linkVariant -> installVariant -> assembleVariant [dir=back, style=dashed]
  compileVariantSwift[label=<compile<i>Variant</i>Swift>]
  linkVariant[label=<link<i>Variant</i>>]
  installVariant[label=<install<i>Variant</i>>]
  assembleVariant[label=<assemble<i>Variant</i>>]

xctest-variant-task-graph.png...

  rankdir=LR

  compileVariantSwift -> {linkVariant, createVariant} -> assembleVariant [dir=back, style=dashed]
  compileVariantSwift[label=<compile<i>Variant</i>Swift>]
  linkVariant[label=<link<i>Variant</i>>]
  createVariant[label=<create<i>Variant</i>>]
  assembleVariant[label=<assemble<i>Variant</i>>]

  // Adds linkage text between link* and create*
  linkVariant -> linkageText -> createVariant [style=invis]

  rankdir=LR

  compileVariantCpp -> {linkVariant, createVariant} -> assembleVariant [dir=back, style=dashed]
  compileVariantCpp[label=<compile<i>Variant</i>Cpp>]
  linkVariant[label=<link<i>Variant</i>>]
  createVariant[label=<create<i>Variant</i>>]
  assembleVariant[label=<assemble<i>Variant</i>>]

  // Adds linkage text between link* and create*
  linkVariant -> linkageText -> createVariant [style=invis]