// reporting).
func (check *Checker) newAliasInstance(pos syntax.Pos, orig *Alias, targs []Type, ctxt *Context) *Alias {
	assert(len(targs) > 0)
	obj := NewTypeName(pos, orig.obj.pkg, orig.obj.name, nil)
	rhs := check.subst(pos, orig.fromRHS, makeSubstMap(orig.TypeParams().list(), targs), nil, ctxt)
	res := check.newAlias(obj, rhs)
	res.orig = orig
	res.tparams = orig.tparams
	res.targs = newTypeList(targs)
	return res
}

				// directly or indirectly, after expansion of the RHS.
				// Therefore t.Origin() must be invalid, no matter how it is
				// instantiated since the instantiation t of t.Origin() happens
				// inside t.Origin()'s RHS and thus is always the same and always
				// present.
				// Therefore we can mark the underlying of both t and t.Origin()

	if err != nil {
		return nil, &UnknownRevisionError{Rev: rev}
	}
	info, err := r.cmd.parseStat(rev, string(out))
	if err != nil {
		return nil, err
	}
	if info.Origin == nil {
		info.Origin = new(Origin)
	}
	info.Origin.VCS = r.cmd.vcs
	info.Origin.URL = r.remote
	return info, nil
}

func (r *vcsRepo) Latest(ctx context.Context) (*RevInfo, error) {
	return r.Stat(ctx, "latest")
}

	origm := t.inst.orig.Method(i)
	assert(origm != nil)

	check := t.check
	// Ensure that the original method is type-checked.
	if check != nil {
		check.objDecl(origm, nil)
	}

	origSig := origm.typ.(*Signature)
	rbase, _ := deref(origSig.Recv().Type())

	// If rbase is t, then origm is already the instantiated method we're looking
	// for. In this case, we return origm to preserve the invariant that

	Sum        string           `json:",omitempty"` // checksum for path, version (as in go.sum)
	GoModSum   string           `json:",omitempty"` // checksum for go.mod (as in go.sum)
	Origin     *codehost.Origin `json:",omitempty"` // provenance of module
	Reuse      bool             `json:",omitempty"` // reuse of old module info is safe
}

type ModuleError struct {
	Err string // error text
}

The methods [Alias.Origin], [Alias.SetTypeParams], [Alias.TypeParams],

type Tags struct {
	Origin *Origin
	List   []Tag
}

// A Tag describes a single tag in a code repository.
type Tag struct {
	Name string
	Hash string // content hash identifying tag's content, if available
}

// isOriginTag reports whether tag should be preserved
// in the Tags method's Origin calculation.

	defer func() {
		if info.Origin == nil {
			return
		}
		if revInfo == nil {
			revInfo = new(RevInfo)
		} else if revInfo.Origin != nil {
			panic("internal error: RevInfo Origin unexpectedly already populated")
		}

		origin := *info.Origin
		revInfo.Origin = &origin
		origin.Subdir = r.codeDir

		v := revInfo.Version

		// careful not to call any methods that would cause t to be expanded: doing
		// so would result in deadlock.
		//
		// So we call t.Origin().TypeParams() rather than t.TypeParams().
		orig := t.Origin()
		n := orig.TypeParams().Len()
		if n == 0 {
			return t // type is not parameterized
		}

		if t.TypeArgs().Len() != n {
			return Typ[Invalid] // error reported elsewhere
		}

func (obj *Var) IsField() bool { return obj.isField }

// Origin returns the canonical Var for its receiver, i.e. the Var object
// recorded in Info.Defs.
//
// For synthetic Vars created during instantiation (such as struct fields or
// function parameters that depend on type arguments), this will be the
// corresponding Var on the generic (uninstantiated) type. For all other Vars
// Origin returns the receiver.
func (obj *Var) Origin() *Var {