// or nil if not found.
//
// For dot-imports, the package name is ".".
//
// Precondition: the Defs and Implicts maps are populated.
func (info *Info) PkgNameOf(imp *ast.ImportSpec) *PkgName {
	var obj Object
	if imp.Name != nil {
		obj = info.Defs[imp.Name]
	} else {
		obj = info.Implicits[imp]
	}
	pkgname, _ := obj.(*PkgName)
	return pkgname
}

// or nil if not found.
//
// For dot-imports, the package name is ".".
//
// Precondition: the Defs and Implicts maps are populated.
func (info *Info) PkgNameOf(imp *syntax.ImportDecl) *PkgName {
	var obj Object
	if imp.LocalPkgName != nil {
		obj = info.Defs[imp.LocalPkgName]
	} else {
		obj = info.Implicits[imp]
	}
	pkgname, _ := obj.(*PkgName)
	return pkgname
}

	var dict readerDict

	{
		r := pr.tempReader(pkgbits.RelocObjDict, idx, pkgbits.SyncObject1)
		if implicits := r.Len(); implicits != 0 {
			errorf("unexpected object with %v implicit type parameter(s)", implicits)
		}

		dict.bounds = make([]typeInfo, r.Len())
		for i := range dict.bounds {
			dict.bounds[i] = r.typInfo()
		}

	for _, test := range tests {
		info := Info{
			Implicits: make(map[syntax.Node]Object),
		}
		name := mustTypecheck(test.src, nil, &info).Name()

		// the test cases expect at most one Implicits entry
		if len(info.Implicits) > 1 {
			t.Errorf("package %s: %d Implicits entries found", name, len(info.Implicits))
			continue
		}

		// extract Implicits entry, if any
		var got string

	}

	for _, test := range tests {
		info := Info{
			Implicits: make(map[ast.Node]Object),
		}
		name := mustTypecheck(test.src, nil, &info).Name()

		// the test cases expect at most one Implicits entry
		if len(info.Implicits) > 1 {
			t.Errorf("package %s: %d Implicits entries found", name, len(info.Implicits))
			continue
		}

		// extract Implicits entry, if any
		var got string

		GoVersion: cfg.GoVersion,
	}
	info := &types.Info{
		Types:      make(map[ast.Expr]types.TypeAndValue),
		Defs:       make(map[*ast.Ident]types.Object),
		Uses:       make(map[*ast.Ident]types.Object),
		Implicits:  make(map[ast.Node]types.Object),
		Instances:  make(map[*ast.Ident]types.Instance),
		Scopes:     make(map[ast.Node]*types.Scope),
		Selections: make(map[*ast.SelectorExpr]*types.Selection),
	}

	info := Info{
		Types:        make(map[ast.Expr]TypeAndValue),
		Instances:    make(map[*ast.Ident]Instance),
		Defs:         make(map[*ast.Ident]Object),
		Uses:         make(map[*ast.Ident]Object),
		Implicits:    make(map[ast.Node]Object),
		Selections:   make(map[*ast.SelectorExpr]*Selection),
		Scopes:       make(map[ast.Node]*Scope),
		FileVersions: make(map[*ast.File]string),
	}

	// typecheck

	info := Info{
		Types:        make(map[syntax.Expr]TypeAndValue),
		Instances:    make(map[*syntax.Name]Instance),
		Defs:         make(map[*syntax.Name]Object),
		Uses:         make(map[*syntax.Name]Object),
		Implicits:    make(map[syntax.Node]Object),
		Selections:   make(map[*syntax.SelectorExpr]*Selection),
		Scopes:       make(map[syntax.Node]*Scope),
		FileVersions: make(map[*syntax.PosBase]string),
	}

	// typecheck

	assert(obj != nil)
	if m := check.Uses; m != nil {
		m[id] = obj
	}
}

func (check *Checker) recordImplicit(node syntax.Node, obj Object) {
	assert(node != nil)
	assert(obj != nil)
	if m := check.Implicits; m != nil {
		m[node] = obj
	}
}

func (check *Checker) recordSelection(x *syntax.SelectorExpr, kind SelectionKind, recv Type, obj Object, index []int, indirect bool) {

	assert(obj != nil)
	if m := check.Uses; m != nil {
		m[id] = obj
	}
}

func (check *Checker) recordImplicit(node ast.Node, obj Object) {
	assert(node != nil)
	assert(obj != nil)
	if m := check.Implicits; m != nil {
		m[node] = obj
	}
}

func (check *Checker) recordSelection(x *ast.SelectorExpr, kind SelectionKind, recv Type, obj Object, index []int, indirect bool) {