return []string{"invalid datetime"}
			}
			return nil
		},
		MaxRegexSize: len(strfmt.DateTimePattern),
	},
}

var formatLibraryDecls = map[string][]cel.FunctionOpt{
	"validate": {
		cel.MemberOverload("format-validate", []*cel.Type{apiservercel.FormatType, cel.StringType}, cel.OptionalType(cel.ListType(cel.StringType)), cel.BinaryBinding(formatValidate)),
	},
	"format.named": {