// compare err and the target and not call [Unwrap] on either.
func Is(err, target error) bool {
	if err == nil || target == nil {
		return err == target
	}

	isComparable := reflectlite.TypeOf(target).Comparable()
	return is(err, target, isComparable)
}

func is(err, target error, targetComparable bool) bool {
	for {
		if targetComparable && err == target {
			return true
		}

// IsMethodSet reports whether the interface t is fully described by its method set.
func (s *_TypeSet) IsMethodSet() bool { return !s.comparable && s.terms.isAll() }

// IsComparable reports whether each type in the set is comparable.
func (s *_TypeSet) IsComparable(seen map[Type]bool) bool {
	if s.terms.isAll() {
		return s.comparable
	}
	return s.is(func(t *term) bool {
		return t != nil && comparable(t.typ, false, seen, nil)
	})
}

// IsMethodSet reports whether the interface t is fully described by its method set.
func (s *_TypeSet) IsMethodSet() bool { return !s.comparable && s.terms.isAll() }

// IsComparable reports whether each type in the set is comparable.
func (s *_TypeSet) IsComparable(seen map[Type]bool) bool {
	if s.terms.isAll() {
		return s.comparable
	}
	return s.is(func(t *term) bool {
		return t != nil && comparable(t.typ, false, seen, nil)
	})
}

			*cause = check.sprintf("%s does not %s %s %s", V, verb, T, *cause)
		}
		return false
	}

	// Only check comparability if we don't have a more specific error.
	checkComparability := func() bool {
		if !Ti.IsComparable() {
			return true
		}
		// If T is comparable, V must be comparable.
		// If V is strictly comparable, we're done.
		if comparable(V, false /* strict comparability */, nil, nil) {
			return true
		}

			*cause = check.sprintf("%s does not %s %s %s", V, verb, T, *cause)
		}
		return false
	}

	// Only check comparability if we don't have a more specific error.
	checkComparability := func() bool {
		if !Ti.IsComparable() {
			return true
		}
		// If T is comparable, V must be comparable.
		// If V is strictly comparable, we're done.
		if comparable(V, false /* strict comparability */, nil, nil) {
			return true
		}

			if reportf != nil {
				reportf("%s cannot be compared", t)
			}
			return false
		}
		return true
	case *Interface:
		if dynamic && !isTypeParam(T) || t.typeSet().IsComparable(seen) {
			return true
		}
		if reportf != nil {
			if t.typeSet().IsEmpty() {
				reportf("empty type set")
			} else {
				reportf("incomparable types in type set")
			}
		}
		// fallthrough

			if reportf != nil {
				reportf("%s cannot be compared", t)
			}
			return false
		}
		return true
	case *Interface:
		if dynamic && !isTypeParam(T) || t.typeSet().IsComparable(seen) {
			return true
		}
		if reportf != nil {
			if t.typeSet().IsEmpty() {
				reportf("empty type set")
			} else {
				reportf("incomparable types in type set")
			}
		}
		// fallthrough