msg = "array length %s must be integer"
	}
	check.errorf(&x, InvalidArrayLen, msg, &x)
	return -1
}

// typeList provides the list of types corresponding to the incoming expression list.
// If an error occurred, the result is nil, but all list elements were type-checked.
func (check *Checker) typeList(list []syntax.Expr) []Type {
	res := make([]Type, len(list)) // res != nil even if len(list) == 0
	for i, x := range list {

}

// instance holds information that is only necessary for instantiated named
// types.
type instance struct {
	orig            *Named    // original, uninstantiated type
	targs           *TypeList // type arguments
	expandedMethods int       // number of expanded methods; expandedMethods <= len(orig.methods)
	ctxt            *Context  // local Context; set to nil after full expansion
}

	// targs and xlist are the type arguments and corresponding type expressions, or nil.
	var targs []Type
	var xlist []syntax.Expr
	if inst != nil {
		xlist = syntax.UnpackListExpr(inst.Index)
		targs = check.typeList(xlist)
		if targs == nil {
			x.mode = invalid
			return nil, nil
		}
		assert(len(targs) == len(xlist))
	}

	// Check the number of type arguments (got) vs number of type parameters (want).

}

// instance holds information that is only necessary for instantiated named
// types.
type instance struct {
	orig            *Named    // original, uninstantiated type
	targs           *TypeList // type arguments
	expandedMethods int       // number of expanded methods; expandedMethods <= len(orig.methods)
	ctxt            *Context  // local Context; set to nil after full expansion
}

	// targs and xlist are the type arguments and corresponding type expressions, or nil.
	var targs []Type
	var xlist []ast.Expr
	if ix != nil {
		xlist = ix.Indices
		targs = check.typeList(xlist)
		if targs == nil {
			x.mode = invalid
			return nil, nil
		}
		assert(len(targs) == len(xlist))
	}

	// Check the number of type arguments (got) vs number of type parameters (want).

// function instantiations. For type instantiations, [Type] will be of dynamic
// type *[Named]. For function instantiations, [Type] will be of dynamic type
// *Signature.
type Instance struct {
	TypeArgs *TypeList
	Type     Type
}

// An Initializer describes a package-level variable, or a list of variables in case
// of a multi-valued initialization expression, and the corresponding initialization
// expression.

// function instantiations. For type instantiations, Type will be of dynamic
// type *Named. For function instantiations, Type will be of dynamic type
// *Signature.
type Instance struct {
	TypeArgs *TypeList
	Type     Type
}

// An Initializer describes a package-level variable, or a list of variables in case
// of a multi-valued initialization expression, and the corresponding initialization
// expression.