type actionDesc struct {
	pos    poser
	format string
	args   []interface{}
}

// A Checker maintains the state of the type checker.
// It must be created with NewChecker.
type Checker struct {
	// package information
	// (initialized by NewChecker, valid for the life-time of checker)
	conf *Config
	ctxt *Context // context for de-duplicating instances
	pkg  *Package
	*Info

type actionDesc struct {
	pos    positioner
	format string
	args   []any
}

// A Checker maintains the state of the type checker.
// It must be created with [NewChecker].
type Checker struct {
	// package information
	// (initialized by NewChecker, valid for the life-time of checker)
	conf *Config
	ctxt *Context // context for de-duplicating instances
	fset *token.FileSet
	pkg  *Package
	*Info

// Package types2 declares the data types and implements
// the algorithms for type-checking of Go packages. Use
// Config.Check to invoke the type checker for a package.
// Alternatively, create a new type checker with NewChecker
// and invoke it incrementally by calling Checker.Files.
//
// Type-checking consists of several interdependent phases:
//
// Name resolution maps each identifier (syntax.Name) in the program to the

// Package types declares the data types and implements
// the algorithms for type-checking of Go packages. Use
// [Config.Check] to invoke the type checker for a package.
// Alternatively, create a new type checker with [NewChecker]
// and invoke it incrementally by calling [Checker.Files].
//
// Type-checking consists of several interdependent phases:
//
// Name resolution maps each identifier ([ast.Ident]) in the program

	var conf Config
	info := &Info{Defs: make(map[*syntax.Name]Object)}
	check := NewChecker(&conf, NewPackage("", "p"), info)
	if err := check.Files([]*syntax.File{f1, f2}); err != nil {
		t.Fatal(err)
	}
	want := printInfo(info)

	// type-check incrementally
	info = &Info{Defs: make(map[*syntax.Name]Object)}
	check = NewChecker(&conf, NewPackage("", "p"), info)
	if err := check.Files([]*syntax.File{f1}); err != nil {

	var conf Config
	info := &Info{Defs: make(map[*ast.Ident]Object)}
	check := NewChecker(&conf, fset, NewPackage("", "p"), info)
	if err := check.Files([]*ast.File{f1, f2}); err != nil {
		t.Fatal(err)
	}
	want := printInfo(info)

	// type-check incrementally
	info = &Info{Defs: make(map[*ast.Ident]Object)}
	check = NewChecker(&conf, fset, NewPackage("", "p"), info)
	if err := check.Files([]*ast.File{f1}); err != nil {

pkg go/types, func MissingMethod(Type, *Interface, bool) (*Func, bool)
pkg go/types, func NewArray(Type, int64) *Array
pkg go/types, func NewChan(ChanDir, Type) *Chan
pkg go/types, func NewChecker(*Config, *token.FileSet, *Package, *Info) *Checker
pkg go/types, func NewConst(token.Pos, *Package, string, Type, constant.Value) *Const
pkg go/types, func NewField(token.Pos, *Package, string, Type, bool) *Var