Dart Docs

Dart

Dart is a client-optimized language for fast apps on any platform. It is an object-oriented, class-based, garbage-collected language with C-style syntax. Dart supports sound null safety, asynchronous programming with Future and Stream, concurrency via isolates, pattern matching, records, and more. It compiles to native ARM/x64, JavaScript, and WebAssembly (WasmGC).

Specification: Dart 3.12 Documentation

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Quick Reference

| Topic | File | |------|------| | Introduction (main, variables, control flow, comments, imports, classes) | introduction.md | | Comments (single-line, multi-line, documentation comments) | comments.md | | Variables (var, final, const, late, type inference, null) | variables.md | | Operators (arithmetic, equality, relational, type test, assignment, logical, bitwise, shift, conditional, cascade, spread) | operators.md | | Methods (instance methods, operators, getters/setters, abstract methods) | methods.md | | Metadata (annotations, @Deprecated, @override, @pragma, custom annotations) | metadata.md | | Built-in Types (int, double, String, bool, List, Set, Map, Runes, Symbol, null) | built-in-types.md | | Records (positional, named fields, type annotations, equality) | records.md | | Collections (lists, sets, maps, spread, collection-if, collection-for) | collections.md | | Generics (generic types, methods, bounds, variance) | generics.md | | Typedefs (type aliases, function type aliases) | typedefs.md | | Type System (sound typing, static checking, runtime checks, type inference) | type-system.md | | Patterns (matching, destructuring, pattern types, switch expressions) | patterns.md | | Pattern Types (logical-or, logical-and, relational, cast, null-check, null-assert, constant, variable, identifier, list, map, record, object) | pattern-types.md | | Control Flow (loops, branches, error handling) | control-flow.md | | Functions (parameters, named, optional, default, closures, generators, async) | functions.md | | Language Versioning (SDK constraints, per-file overrides, migration) | language-versioning.md | | Libraries & Imports (import, export, part, show/hide, deferred, privacy) | libraries.md | | Classes (instance variables, methods, static, abstract, implicit interfaces, noSuchMethod) | classes.md | | Constructors (generative, named, const, factory, redirecting, initializing formals, super) | constructors.md | | Primary Constructors (var/final declaring parameters, scoping, named, const, private named params) | primary-constructors.md | | Inheritance & Mixins (extends, override, super, mixins, mixin class, on clause) | inheritance-mixins.md | | Enums (simple, enhanced, with members, mixins, sealed) | enums.md | | Extension Methods & Types (extensions, extension types) | extensions.md | | Dot Shorthands (.foo syntax, context type inference, enum/static/constructor shorthands) | dot-shorthands.md | | Callable Objects (call() method, emulating functions) | callable-objects.md | | Class Modifiers (abstract, base, final, interface, sealed, mixin) | class-modifiers.md | | Concurrency (event loop, isolates, Isolate.run, message passing) | concurrency.md | | Isolates (Isolate.run, Isolate.spawn, ReceivePort, SendPort, web concurrency) | isolates.md | | Async Programming (Future, async/await, Stream, StreamController, zones) | async.md | | Using Streams (await for, listen, single-subscription, broadcast, error handling) | using-streams.md | | Futures & Error Handling (then, catchError, whenComplete, common pitfalls) | futures-error-handling.md | | Null Safety (non-nullable by default, ? type, ! operator, late, null checks) | null-safety.md | | Keywords (all reserved words, context-dependent keywords) | keywords.md | | Core Libraries (dart:core, dart:async, dart:math, dart:convert, dart:io, dart:jsinterop) | core-libraries.md | | Iterable Collections (reading, filtering, mapping, lazy evaluation) | iterable-collections.md | | Creating Streams (async*, StreamController, StreamTransformer, broadcast) | creating-streams.md | | Effective Dart (style, documentation, usage, design best practices) | effective-dart.md | | Packages (pub, pubspec.yaml, dependencies, publishing, workspaces, hooks) | packages.md | | Development (server apps, web apps, Wasm, JSON serialization, Google Cloud) | development.md | | Interoperability (dart:ffi, C interop, JS interop, Objective-C/Swift, Java/Kotlin) | interop.md | | Tools (Dart SDK CLI, dart analyze, build, compile, format, test, DevTools, DartPad) | tools.md | | buildrunner (code generation, builders, build/watch/serve/test commands) | build-runner.md | | Static Analysis (analysis_options.yaml, linter rules, diagnostics, analyzer plugins) | static-analysis.md | | Testing (unit, component, integration tests, dart test, test package) | testing.md |

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Core Concepts

• Sound Null Safety: Types are non-nullable by default. Use ? for nullable types. The analyzer catches null errors at compile time.
• Type Inference: Use var for local variables; types are inferred from initializers. Use explicit types for public APIs.
• Object-Oriented: Every object is an instance of a class. All classes descend from Object. Mixin-based inheritance.
• Async Programming: Future and Stream for async operations. async/await for clean async code.
• Isolates: Dart's concurrency model — independent workers with their own memory and event loop. No shared memory between isolates.
• Patterns & Records: Pattern matching and destructuring with switch expressions, if-case, variable declarations. Records are anonymous, immutable, aggregate types.
• Class Modifiers: abstract, base, final, interface, sealed, mixin control how classes can be used from other libraries.
• Extension Methods & Types: Add functionality to existing libraries without modifying them. Extension types for zero-cost wrappers.
• Generics: Reified generic types — type parameters are available at runtime. Covariant by default.
• Libraries & Privacy: Every Dart file is a library. Identifiers starting with _ are library-private.
• FFI & JS Interop: dart:ffi for calling C libraries. dart:js_interop for JavaScript/WebAssembly interop.
• Pub: Dart's package manager. pubspec.yaml defines dependencies and metadata. Packages hosted on pub.dev.

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Official Documentation

• Dart Documentation
• Dart Language Tour
• Dart Core Libraries
• Effective Dart
• Dart API Reference
• DartPad (Online Editor)
• pub.dev (Package Site)
• Dart Language Specification
• Dart Cheatsheet
• Dart Blog

Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: pledgeandgrow
• Source: pledgeandgrow/pledge-skills
• License: MIT

Install and usage instructions live in the source repository linked above.