dart2.serialization.native.native_enum.mustache Maven / Gradle / Ivy
{{#description}}/// {{{.}}}{{/description}}
class {{{classname}}} {
/// Instantiate a new enum with the provided [value].
const {{{classname}}}._(this.value);
/// The underlying value of this enum member.
final {{{dataType}}} value;
@override
String toString() => {{#isString}}value{{/isString}}{{^isString}}value.toString(){{/isString}};
{{{dataType}}} toJson() => value;
{{#allowableValues}}
{{#enumVars}}
static const {{{name}}} = {{{classname}}}._({{#isString}}r{{/isString}}{{{value}}});
{{/enumVars}}
{{/allowableValues}}
/// List of all possible values in this [enum][{{{classname}}}].
static const values = <{{{classname}}}>[
{{#allowableValues}}
{{#enumVars}}
{{{name}}},
{{/enumVars}}
{{/allowableValues}}
];
static {{{classname}}}? fromJson(dynamic value) => {{{classname}}}TypeTransformer().decode(value);
static List<{{{classname}}}> listFromJson(dynamic json, {bool growable = false,}) {
final result = <{{{classname}}}>[];
if (json is List && json.isNotEmpty) {
for (final row in json) {
final value = {{{classname}}}.fromJson(row);
if (value != null) {
result.add(value);
}
}
}
return result.toList(growable: growable);
}
}
/// Transformation class that can [encode] an instance of [{{{classname}}}] to {{{dataType}}},
/// and [decode] dynamic data back to [{{{classname}}}].
class {{{classname}}}TypeTransformer {
factory {{{classname}}}TypeTransformer() => _instance ??= const {{{classname}}}TypeTransformer._();
const {{{classname}}}TypeTransformer._();
{{{dataType}}} encode({{{classname}}} data) => data.value;
/// Decodes a [dynamic value][data] to a {{{classname}}}.
///
/// If [allowNull] is true and the [dynamic value][data] cannot be decoded successfully,
/// then null is returned. However, if [allowNull] is false and the [dynamic value][data]
/// cannot be decoded successfully, then an [UnimplementedError] is thrown.
///
/// The [allowNull] is very handy when an API changes and a new enum value is added or removed,
/// and users are still using an old app with the old code.
{{{classname}}}? decode(dynamic data, {bool allowNull = true}) {
if (data != null) {
switch (data) {
{{#allowableValues}}
{{#enumVars}}
case {{#isString}}r{{/isString}}{{{value}}}: return {{{classname}}}.{{{name}}};
{{/enumVars}}
{{/allowableValues}}
default:
if (!allowNull) {
throw ArgumentError('Unknown enum value to decode: $data');
}
}
}
return null;
}
/// Singleton [{{{classname}}}TypeTransformer] instance.
static {{{classname}}}TypeTransformer? _instance;
}