Online Dart Compiler Features
Sound Null Safety
- Dart 3's null safety prevents crashes—variables are non-nullable by default, null only when marked with ?
- Compile-time null checks catch errors early—no runtime null pointer exceptions in production
- Late variables for deferred initialization—use late keyword when value is not available at declaration
- Null assertion operator ! for guaranteed non-null—tell compiler you know value exists
Async Programming
- Future for single async values—handle network requests, file I/O patterns, and delayed operations
- Async/await syntax for readable code—write asynchronous logic that looks synchronous
- Stream for multiple async values—handle event sequences like user input or real-time data
- Practice Flutter patterns—master async code critical for mobile app development
Modern Language Features
- Records for grouped values—return multiple values from functions without creating classes
- Pattern matching in switch—destructure records and objects with elegant pattern syntax
- Cascade notation .. chains method calls—modify objects fluently without repeating variable names
- Collection if and for—build lists and maps conditionally with inline control flow
Flutter Development Foundation
- Learn Dart before Flutter—understand language fundamentals critical for mobile development
- Practice Flutter design patterns—mixins, extension methods, and factory constructors
- Test Dart algorithms without Flutter overhead—focus purely on logic and data structures
- Share Dart solutions with Flutter community—great for getting feedback before UI implementation
Dart Keyboard Shortcuts
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Get started freeFrequently Asked Questions
What version of Dart does this compiler support?
This Dart compiler runs Dart 3.5, featuring sound null safety, record types, pattern matching, and all modern language improvements. Write production-ready Dart code with the latest syntax and features.
Is this good for learning Flutter?
Absolutely! While this Dart compiler does not run Flutter UI frameworks, it is perfect for mastering Dart fundamentals—null safety, async/await, collections, OOP—that are essential before Flutter development. Learn Dart syntax without Flutter complexity.
What is sound null safety in Dart?
Sound null safety means variables cannot be null unless explicitly marked with ?. Dart 3 enforces this at compile-time, preventing null reference errors before runtime. Use String? for nullable types, String for guaranteed non-null values.
Can I use async/await in this Dart compiler?
Yes! Practice async and await keywords with Future and Stream types. While actual I/O operations are limited in browser environments, you can test async patterns, error handling, and understand asynchronous Dart code structure perfectly.
What Dart libraries are available?
Full access to dart:core (List, Map, Set, String, DateTime), dart:math, dart:collection, and dart:convert. No Flutter packages or pub.dev dependencies—focus on core Dart language and standard library functionality.
How does Dart compare to JavaScript?
Dart is strongly typed with compile-time type checking (JavaScript is dynamically typed). Dart has sound null safety built-in. Both support async/await. Dart compiles to native code for mobile apps via Flutter, while JavaScript runs in web browsers primarily.
Can I prepare for Flutter interviews with this?
Yes! This Dart compiler is perfect for Flutter developer interviews. Test Dart algorithms, null safety handling, async patterns, and OOP concepts. Share solutions via URLs. Master Dart before tackling Flutter-specific UI questions.
What are cascade notation and method chaining?
Cascade notation (..) lets you call multiple methods on the same object without repeating the variable. For example: person..name = 'Alice'..age = 30..greet() calls all methods on person. Cleaner than person.name = 'Alice'; person.age = 30; person.greet();
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