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Variables and Constants Declaration

Everything you need to declare variables and constants in Flow-Wing, with examples.

Variable Declaration​

Declare a variable by giving it a type and a value.

Example:​

var integer: int = 10
var decimal: deci = 5.5
var _string: str = "Hello, Flow-Wing!"
var _boolean: bool = true
var someThing = "Hello, Flow-Wing!"

someThing is a dynamic type variable — it can hold any value. Right now it holds "Hello, Flow-Wing!", a string.

Typed Variables​

Give a variable an explicit type, then assign a value at runtime.

Example:​

var number: int = 2
var string: str = "Hello, Flow-Wing!"
var boolean: bool = true

Example with Complex Type:​

type Person = {
  name: str
  age: int
  height: deci
}
var person: Person = {
  name: "Alice",
  age: 30,
  height: 5.5
}
print(person)

Example with Array Type:​

var numbers: int[5] = [1, 2, 3, 4, 5]

Example with Default Value:​

var numbers: int[5]

Here numbers is an array of int with a default value of [0, 0, 0, 0, 0].

Variable Scope​

Variables live inside the block { } where you declare them:

{
  var x: int = 10
  print(x)  /; 10
}
/; x is out of scope here — gone

Outer variables are visible inside inner blocks. Inner blocks can shadow outer variables by declaring the same name:

var x: int = 10
{
  var x: int = 20  /; shadows outer x
  print(x)  /; 20
}
print(x)  /; 10

Constant Declaration​

Constants lock in a value at compile time. Use const for values that never change — the compiler optimizes them, and nobody accidentally reassigns them:

Example:​

const maxUsers: int = 100
/; maxUsers = 200  /; Error: cannot reassign constant