- 01Setting up (what you'll need)
- 02Your first output (print)
- 03Variables and types (var and annotations)
- 04Null safety (? and !)
- 05Branching (the if statement)
- 06Repeating (the for loop)
- 07Writing your own function
- 08Repeating (the while loop)
- 09Working with lists (List)
- 10Working with maps (Map)
- 11Classes (object orientation)
- 12Constructors
- 13Inheritance
- 14Named arguments
- 15Asynchronous work (Future, async, await)
- 16Working with strings
- 17The switch statement
- 18The ternary operator
- 19Extension methods
- 20[Project] Build a small inventory system
Writing your own function
This lesson covers the basic form for defining a function in Dart.
A function is defined as returnType name(args) { ... }. If the body is a single expression, you can also use the shorter arrow form with =>.
The sample code defines String greet(String name) { ... }, which takes a name and returns a greeting built from it.
A common early stumble is a mismatch between the declared return type and the type of the value actually returned. Dart is statically typed, so it reports the mismatch as an error before the program runs.
In professional work, functions are used everywhere — including for assembling the screen components (widgets) of a Flutter app.
๐งช This site can't compile or run Dart directly, so it checks on the spot whether what you typed matches the reference code (scoring happens entirely in your browser โ nothing is sent anywhere).