}
	}).describef(atPos(pos), "verify instantiation")

	return inst
}

func (check *Checker) callExpr(x *operand, call *ast.CallExpr) exprKind {
	ix := typeparams.UnpackIndexExpr(call.Fun)
	if ix != nil {
		if check.indexExpr(x, ix) {
			// Delay function instantiation to argument checking,
			// where we combine type and value arguments for type
			// inference.

		case novalue:
			check.errorf(&x, NotAType, "%s used as type", &x)
		default:
			check.errorf(&x, NotAType, "%s is not a type", &x)
		}

	case *ast.IndexExpr, *ast.IndexListExpr:
		ix := typeparams.UnpackIndexExpr(e)
		check.verifyVersionf(inNode(e, ix.Lbrack), go1_18, "type instantiation")
		return check.instantiatedType(ix, def)

	case *ast.ParenExpr:

			ptr = true
			rtyp = t.X
		default:
			break L
		}
	}

	// unpack type parameters, if any
	switch rtyp.(type) {
	case *ast.IndexExpr, *ast.IndexListExpr:
		ix := typeparams.UnpackIndexExpr(rtyp)
		rtyp = ix.X
		if unpackParams {
			for _, arg := range ix.Indices {
				var par *ast.Ident
				switch arg := arg.(type) {
				case *ast.Ident:
					par = arg
				case *ast.BadExpr: