val variableName = value
var variableName = value

// Explicit type
val variableName: type = value

// Wrong: compiler can't infer the type without a value
val variableName

// Wrong: val is immutable
val variableName = 1
variableName = 2

Default Types

Type	Description
Int	Whole numbers from -9,223,372,036,854,775,808 to 9,223,372,036,854,775,807. Character literals (e.g. `a`) are also stored as `Int`.
Float	Fractional numbers. Sufficient for 15–16 decimal digits.
Bool	Stores `true` or `false`.
String	Stores a sequence of characters.
Any	Stores any object (testing).

Character Literals

In Autolang, there is no separate Char type. Single-quote character literals evaluate directly to their Int (ASCII) values.

val codeA = 'a' // codeA is Int with value 97
val codeB = 'b' // codeB is Int with value 98

println(codeA + 1 == codeB) // Output: true

Nullable Types

Append ? to a type to allow null. Use ! to assert non-null.

val variableName: type?        // Nullable, default null
var variableName: type?        // Nullable, mutable
val variableName? = value      // Inferred nullable
val variableName! = value      // Inferred non-nullable

Assignment & Copying

Int values are automatically copied on assignment (passed by value). Other object types are references by default. To share a mutable reference to an Int, wrap it in a class.

var a = 5
var b = a       // b gets a copy of a
b += 1
println(a)      // 5 (unchanged)

// Use a wrapper class to share a mutable reference
class Box<T>(var value: T)
val boxA = Box<Int>(10)
val boxB = boxA  // both point to the same Box
boxB.value += 5
println(boxA.value) // 15

String Concatenation with Objects

When you concatenate an object with a String using +, Autolang automatically calls toString() on that object.

class User(val username: String) {
    fun toString(): String = "User: " + username
}

val u = User("bob")
println(u + " is logged in")  // Output: User: bob is logged in
println("Welcome, " + u)      // Output: Welcome, User: bob

Example

val name = "John"       // String
val age = 18            // Int
val char: Int = 'A'    // Character literal as Int (65)
val money: Float = 4.5 // Float
val email! = """autolang@gmail.com
"""
val child: Int?        // Null value

println("Hello everyone, my name is " + name + " and I'm " + age)
println("Hello everyone, my name is ${name} and I'm ${age}")
println("Now I have $money dollar and my email is $email")

if (child == null) {
  println("I don't have any childs")
} else {
  println("I have some childs")
}

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