Custom Libraries
Custom Libraries
About
- Code Organization: Logical grouping
- Privacy Control: Hide implementation
- Reusability: Share across projects
- Structure: Multiple files
Main Topics
-
Library Declaration
- Definition:
library
keyword - Example:
library my_awesome_library;
- Definition:
-
Part Files
- Definition: Split implementation
- Example:
part 'src/implementation.dart'; part 'src/helpers.dart';
-
Export Directives
- Definition: Public API
- Example:
export 'src/public.dart'; export 'src/types.dart';
-
Private Implementation
- Definition:
src/
directory - Example:
lib/ my_library.dart src/ implementation.dart
- Definition:
-
Documentation
- Definition: API docs
- Example:
/// A utility library for string operations library string_utils;
How to Use
- Structure: Logical modules
- Privacy: Hide implementation
- Documentation: Explain purpose
- Testing: Test public API
How It Works
- Scope: Library boundary
- Privacy:
_
prefix - Composition: Parts form one library
- Distribution: Via packages
Example:
// lib/weather.dart
library weather;
export 'src/models.dart';
export 'src/api.dart';
export 'src/exceptions.dart';
// Implementation files in src/
Conclusion
Custom libraries in Dart enable clean code organization through logical grouping and controlled visibility. By using library declarations, part files, and export directives, developers can create well-structured, maintainable codebases with clear public APIs.