u.setHandle(x, hy)
	}
	return true
}

// asBoundTypeParam returns x.(*TypeParam) if x is a type parameter recorded with u.
// Otherwise, the result is nil.
func (u *unifier) asBoundTypeParam(x Type) *TypeParam {
	if x, _ := Unalias(x).(*TypeParam); x != nil {
		if _, found := u.handles[x]; found {
			return x
		}
	}
	return nil
}

				if p.Value == "_" {
					if check.recvTParamMap == nil {
						check.recvTParamMap = make(map[*syntax.Name]*TypeParam)
					}
					check.recvTParamMap[p] = tparams[i]
				}
			}
			// determine receiver type to get its type parameters
			// and the respective type parameter bounds
			var recvTParams []*TypeParam
			if rname != nil {
				// recv should be a Named type (otherwise an error is reported elsewhere)

				if p.Name == "_" {
					if check.recvTParamMap == nil {
						check.recvTParamMap = make(map[*ast.Ident]*TypeParam)
					}
					check.recvTParamMap[p] = tparams[i]
				}
			}
			// determine receiver type to get its type parameters
			// and the respective type parameter bounds
			var recvTParams []*TypeParam
			if rname != nil {
				// recv should be a Named type (otherwise an error is reported elsewhere)

	switch Unalias(t).(type) {
	case *Basic, *Named, *TypeParam:
		return true
	}
	return false
}

// isTypeLit reports whether t is a type literal.
// This includes all non-defined types, but also basic types.
// isTypeLit may be called with types that are not fully set up.
func isTypeLit(t Type) bool {
	switch Unalias(t).(type) {
	case *Named, *TypeParam:
		return false
	}
	return true
}

	switch Unalias(t).(type) {
	case *Basic, *Named, *TypeParam:
		return true
	}
	return false
}

// isTypeLit reports whether t is a type literal.
// This includes all non-defined types, but also basic types.
// isTypeLit may be called with types that are not fully set up.
func isTypeLit(t Type) bool {
	switch Unalias(t).(type) {
	case *Named, *TypeParam:
		return false
	}
	return true
}

	origT := T
	V := Unalias(x.typ)
	T = Unalias(T)

	// x's type is identical to T
	if Identical(V, T) {
		return true, 0
	}

	Vu := under(V)
	Tu := under(T)
	Vp, _ := V.(*TypeParam)
	Tp, _ := T.(*TypeParam)

	// x is an untyped value representable by a value of type T.
	if isUntyped(Vu) {
		assert(Vp == nil)
		if Tp != nil {
			// T is a type parameter: x is assignable to T if it is

	opTypeParam  = 'T' // .TypeParams.At(i) (Named, Signature)
	opConstraint = 'C' // .Constraint()     (TypeParam)

	// type->object operators
	opAt     = 'A' // .At(i)		 (Tuple)
	opField  = 'F' // .Field(i)	 (Struct)
	opMethod = 'M' // .Method(i) (Named or Interface; not Struct: "promoted" names are ignored)
	opObj    = 'O' // .Obj()		 (Named, TypeParam)
)

// For is equivalent to new(Encoder).For(obj).
//

	origT := T
	V := Unalias(x.typ)
	T = Unalias(T)

	// x's type is identical to T
	if Identical(V, T) {
		return true, 0
	}

	Vu := under(V)
	Tu := under(T)
	Vp, _ := V.(*TypeParam)
	Tp, _ := T.(*TypeParam)

	// x is an untyped value representable by a value of type T.
	if isUntyped(Vu) {
		assert(Vp == nil)
		if Tp != nil {
			// T is a type parameter: x is assignable to T if it is

	// bounds is a slice of typeInfos corresponding to the underlying
	// bounds of the element's type parameters.
	bounds []typeInfo

	// tparams is a slice of the constructed TypeParams for the element.
	tparams []*types.TypeParam

	// derived is a slice of types derived from tparams, which may be
	// instantiated while reading the current element.
	derived      []derivedInfo
	derivedTypes []types.Type // lazily instantiated from derived
}

	case *types.Named:
		hash := h.hashPtr(t.Obj())
		targs := t.TypeArgs()
		for i := 0; i < targs.Len(); i++ {
			targ := targs.At(i)
			hash += 2 * h.Hash(targ)
		}
		return hash

	case *types.TypeParam:
		return h.hashTypeParam(t)

	case *types.Tuple:
		return h.hashTuple(t)
	}

	panic(fmt.Sprintf("%T: %v", t, t))
}

func (h Hasher) hashTuple(tuple *types.Tuple) uint32 {