if validate {
		tparams := orig_.TypeParams().list()
		assert(len(tparams) > 0)
		if len(targs) != len(tparams) {
			return nil, fmt.Errorf("got %d type arguments but %s has %d type parameters", len(targs), orig, len(tparams))
		}
		if i, err := (*Checker)(nil).verify(nopos, tparams, targs, ctxt); err != nil {
			return nil, &ArgumentError{i, err}
		}
	}

	if validate {
		tparams := orig_.TypeParams().list()
		assert(len(tparams) > 0)
		if len(targs) != len(tparams) {
			return nil, fmt.Errorf("got %d type arguments but %s has %d type parameters", len(targs), orig, len(tparams))
		}
		if i, err := (*Checker)(nil).verify(nopos, tparams, targs, ctxt); err != nil {
			return nil, &ArgumentError{i, err}
		}
	}

// TypeParamList holds a list of type parameters.
type TypeParamList struct{ tparams []*TypeParam }

// Len returns the number of type parameters in the list.
// It is safe to call on a nil receiver.
func (l *TypeParamList) Len() int { return len(l.list()) }

// At returns the i'th type parameter in the list.
func (l *TypeParamList) At(i int) *TypeParam { return l.tparams[i] }

// list is for internal use where we expect a []*TypeParam.

		// are rare.)
		name := ""
		if len(params) > 0 && params[0].name != "" {
			// name needed
			name = sig.recv.name
			if name == "" {
				name = "_"
			}
		}
		params = append([]*Var{NewVar(sig.recv.pos, sig.recv.pkg, name, x.typ)}, params...)
		x.mode = value
		x.typ = &Signature{
			tparams:  sig.tparams,
			params:   NewTuple(params...),
			results:  sig.results,
			variadic: sig.variadic,

func (a *Alias) TypeParams() *TypeParamList { return a.tparams }

// SetTypeParams sets the type parameters of the alias type a.
// The alias a must not have type arguments.
func (a *Alias) SetTypeParams(tparams []*TypeParam) {
	assert(a.targs == nil)
	a.tparams = bindTParams(tparams)
}

// TypeArgs returns the type arguments used to instantiate the Alias type.

func (a *Alias) TypeParams() *TypeParamList { return a.tparams }

// SetTypeParams sets the type parameters of the alias type a.
// The alias a must not have type arguments.
func (a *Alias) SetTypeParams(tparams []*TypeParam) {
	assert(a.targs == nil)
	a.tparams = bindTParams(tparams)
}

// TypeArgs returns the type arguments used to instantiate the Alias type.

func (r *importReader) kind() itag {
	return itag(r.uint64())
}

func (r *importReader) signature(recv *types.Var, rparams, tparams []*types.TypeParam) *types.Signature {
	params := r.paramList()
	results := r.paramList()
	variadic := params.Len() > 0 && r.bool()
	return types.NewSignatureType(recv, rparams, tparams, params, results, variadic)
}

func (r *importReader) tparamList() []*types.TypeParam {
	n := r.uint64()

		fn.Type.Params == nil ||
		len(fn.Type.Params.List) != 1 ||
		len(fn.Type.Params.List[0].Names) > 1 {
		return
	}

	// The param must look like a *testing.T or *testing.B.
	if !isTestParam(fn.Type.Params.List[0].Type, prefix[:1]) {
		return
	}

	if tparams := fn.Type.TypeParams; tparams != nil && len(tparams.List) > 0 {

func (t *Named) TypeParams() *TypeParamList { return t.resolve().tparams }

// SetTypeParams sets the type parameters of the named type t.
// t must not have type arguments.
func (t *Named) SetTypeParams(tparams []*TypeParam) {
	assert(t.inst == nil)
	t.resolve().tparams = bindTParams(tparams)
}

// TypeArgs returns the type arguments used to instantiate the named type t.

		check.declare(check.scope, name, tname, scopePos)
		tparams = append(tparams, tpar)
	}

	if check.conf._Trace && len(names) > 0 {
		check.trace(names[0].Pos(), "type params = %v", tparams[len(tparams)-len(names):])
	}

	return tparams
}

func (check *Checker) collectMethods(obj *TypeName) {
	// get associated methods