attributes library

Decode and encode structured data type-safely from JSON with data utilities.

Generic data structures for values, identifiers, entities and data objects.

Supports type-safe and null-safe accessors for value properties.

DataObject can represent data like JSON Objects or properties as a map. DataArray can represent data like JSON Arrays or properties as a list.

Usage: import package:attributes/attributes.dart

Classes

Counted

An interface for a collection with countable items.

DataArray

An interface for a data array with property values accessed by int keys (or indexes).

DataElement<K>

An interface for a data element that is a collection with accessors for typed values.

DataObject

An interface for a data object with property values accessed by String keys.

Entity

An interface for an entity with an optional id and required properties (as a data object).

EntityBase

An immutable base implementation of Entity.

Identifier

An interface for an identifier of something, represented as String, int or BigInt.

Primitive

A interface for a primitive value with type and null safe accessors for data.

PrimitiveAccessor<K>

An interface to access typed primitive values by keys of type K.

StringOrInteger

An interface for a value representing String, int or BigInt data.

Value

An interface for a value with type and null safe accessors for data implementing Primitive.

ValueAccessor<K>

An interface to access typed values by keys of type K.

Mixins

ValueAccessorMixin<K>

A base mixin with a partial implementation of ValueAccessor.

Functions

toBigIntValue(Object? data, {BigInt? min, BigInt? max}) → BigInt

Converts data to BigInt or throws FormatException if cannot convert.

toBoolValue(Object? data) → bool

Converts data to bool or throws FormatException if cannot convert.

toDoubleValue(Object? data, {double? min, double? max}) → double

Converts data to double or throws FormatException if cannot convert.

toIdValue(Object? data) → Identifier

Converts data to Identifier or throws FormatException if cannot convert.

toIntValue(Object? data, {int? min, int? max}) → int

Converts data to int or throws FormatException if cannot convert.

toNullableValueMapOf<K extends Object, V extends Object>(Map<K, Object?> map, {bool isExposed = false}) → Map<K, V?>

Converts map to a value map of K to V?, or throws if cannot convert.

toNullableValueOf<T extends Object>(Object? data) → T?

Converts data to a value of T? or throws if cannot convert.

toNullableValuesOf<T extends Object>(Iterable<Object?> list, {bool isExposed = false}) → Iterable<T?>

Converts list to a value iterable of T? or throws if cannot convert.

toNumValue(Object? data, {num? min, num? max}) → num

Converts data to num or throws FormatException if cannot convert.

toStringValue(Object? data) → String

Converts data to String or throws FormatException if cannot convert.

toTimeMillisUTCValue(Object? data, {bool isUTCSource = false}) → DateTime

Converts the data to a DateTime value.

toTimeUTCValue(Object? data, {DateFormat? sourceFormat, bool isUTCSource = false}) → DateTime

Converts the data to a DateTime value.

toValueMapOf<K extends Object, V extends Object>(Map<K, Object?> map, {bool isExposed = false}) → Map<K, V>

Converts map to a value map of K to V, or throws if cannot convert.

toValueOf<T extends Object>(Object? data) → T

Converts data to a value of T or throws FormatException if cannot.

toValuesOf<T extends Object>(Iterable<Object?> list, {bool isExposed = false}) → Iterable<T>

Converts list to a value iterable of T or throws if cannot convert.

Exceptions / Errors

ConversionException

A FormatException notifying about an unsupported conversion.

InvalidValueException

A FormatException notifying about an invalid value

NullValueException

A FormatException notifying about a null value.

UndefinedValueException

A FormatException notifying about an undefined or missing value.