mek_data_class

Description:

mek data class

The purpose of this library is to expose the generation of very simple class methods with excellent performance and little code generation.
For this you will only be able to enable what you need of the supported features
Features #
Auto generation of:

✅ Inheritance and generic classes supported
✅ hashCode and == methods
✅ pretty toString method
✅ copyWith method
✅ *Changes class and change, toChanges methods in data class
✅ *Builder class to build your class

Install package #
To use DataClass, you will need your typical build_runner/code-generator setup.
First, install build_runner, data_class, data_class_generator by adding them to your pubspec.yaml file:
# pubspec.yaml
dependencies:
mek_data_class:

dev_dependencies:
build_runner:
mek_data_class_generator:
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Run the generator #
To run the code generator you can use:

<dart|flutter> pub run build_runner build

As such, a file that wants to use DataClass will start with:
import 'package:mek_data_class/mek_data_class.dart';

part 'my_file.g.dart';
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Usage/Examples #
You can see some examples in

basic
generics
inheritance

Basic #
Because the boiler plate is generated as a mixin, it is minimally intrusive on the interface of the class.
You only have to provide a constructor with named arguments for all fields and extend the generated mixin.
@DataClass()
class Product with _$Product {
final String title;
@DataField(equality: DefaultEquality())
final double price;

const Product({
required this.title,
required this.price,
});

String get titlePrice => '$title$price';
}
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Customization of the equal operator and hashcode through the use of the Equality class is supported. See example.
Inheritance #
Taking into consideration the previous example you can write and inherit all methods
@DataClass()
class PrettyProduct extends Product with _$PrettyProduct {
final String color;

const Product({
required String title,
required double price,
required this.color,
}) : super(title: title, price: price);

String get titlePriceColor => '$titlePrice$color';
}
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Generics #
You can also declare classes with generic types
@DataClass()
class Value<T> with _$Value<T> {
final T value;

const Product({
required this.value,
});
}
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Pretty string #
Use the ClassToString package to perform the toString method
final product = Product(...);
/// Product(
/// title=Overlord,
/// price=12,
/// )
print(product);
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CopyWith #
The classic copyWith, need explanations? No, but try to prefer using *Changes which supports nullability
final product = Product(...);
print(product.copyWith(title: 'Raisekamika'));
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Enable in build.yaml with copyable: true

*Changes #
Unlike a builder you cannot set values to null but the field is not defined as such and cannot be instantiated
final updatedProduct = product.change((changes) => changes..title = 'Raisekamika');

final changes = product.toChanges();
changes.title = 'Raisekamika';
final updatedProduct = changes.build();
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Enable in build.yaml with changeable: true

*Changes.update
Update the *Changes class by passing a function
final updatedChanges = changes.update((c) => c..title = 'Albedo'); // title=Albedo
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*Changes.replace
Update the properties of the *Changes class with the properties of the DataClass
final updatedChanges = productChanges.replace(product); // title=Raisekamika
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*Changes.build
Build the DataClass from *Changes class
Product product = productChanges.build();
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*Builder #
Build your class using a builder.
It is not safe to construct a class using a builder but it allows you to complete the construction whenever you want.
@DataClass(buildable: true)
class Product with _$Product {
final int id;
const Product({required this.id});
factory Product.build(void Function(ProductBuilder b) updates) =>
(ProductBuilder().update(updates)).build();
}

final builder = ProductBuilder();
builder.id = 12;
final product = builder.build();
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DataClassFields #
Generate a class that contains the names of the fields of the Data Class. @DataClass(createFieldsClass)
Example:
@DataClass(createFieldsClass: true)
class Product with _$Product {
final int id;
const Product({required this.id});
}
// GENERATED CODE
class ProductFields {
final String _path;
const ProductFields([this._path = '']);
String get id => '${_path}id';
}
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Global Configs #
See the docs of the DataClass class for more information



Key
Default
Description




page_width
80
adjust the page formatting width of the generated dart code


stringify_if_null
true
if set to false, null values will not be included in the toString


stringify_type
params
if set to fields, fields of a class that are not passed to the constructor will also be included


fields_class_visible
true
if set to false, the fields classes is private



# build.yaml
targets:
$default:
builders:
mek_data_class_generator:data_class:
enabled: true
options:
page_width: 80
comparable: true
stringify: true
stringify_type: params | fields
stringify_if_null: true
buildable: false
copyable: false
changeable: false
changes_visible: false
create_fields_class: false
fields_class_visible: true
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Recommended options #
comparable: true
stringify: true
changeable: true
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Motivations #

Some packages generate a lot of code and mess with the normal, classic class construction in dart.
Also you can't easily select classes without any problem, without having to create mixins for the methods
Some packages require you to mark all your fields with @override


Similar packages freezed, built_value, dataclass_beta, functional_data